(1) Note. Terms having an asterisk (*) are defined in the GLOSSARY, below.
This is the generic class for:
(a) processes consisting of the single or repeated unit operation of forming a single-crystal* of any type of material, including inorganic or organic;
(b) such processes combined with perfecting operations; and
(c) apparatus for conducting non-coating processes of this class.
However, the following classes specifically provide for the unit operation of single-crystal* growth:
Class 505, Class 419; Class 204; and Class 164, subclass 122.2. And the following classes specifically provide for apparatus for single-crystal* growth:
Class 118; Class 204; and Class 422.
B. GUIDE TO USING THIS CLASS DEFINITION
The statements in LINES WITH OTHER CLASSES, below, set forth the precise and controlling class lines.
Unless otherwise indicated, placement according to these class lines is subject to the hierarchical and comprehensive rules of placement.
Class 117 is most broadly organized according to processes and apparatus. Further arrangement is premised on the physical state of the immediate-precursor* (the precursor* material immediately adjacent to the growing single-crystal*).
The descending order of arrangement of the physical state of the immediate-precursor* is: solid or gel state; liquid or supercritical state; vapor or gaseous state. Care must be exercised to correctly identify the physical state of the immediate-precursor* in order to obtain correct placement.
For example, vapor phase deposition of a non-single-crystal* material followed by a single-crystal* forming step from that vapor deposited material would be placed as follows: into a solid state precursor* subclass if that formation step does not change the solid state of the material (such as by melting or liquefying it); into a liquid state precursor* subclass if the material is liquified in the formation step and the single-crystal* is grown from the liquid; into a vapor state precursor* subclass if during the single-crystal* formation step the material is evaporated or sublimed and redeposited to form a single-crystal*.
This class also provides an extensive Cross-Reference Art Collection schedule. A portion of this is loosely based upon the European Patent Office-modified IPC classification. However, where there are indents, the U.S. hierarchical practice of placement in the first appropriate subclass among corresponding indents is followed. Coextensive use of cross-referencing has been used so that this alternative schedule may provide an acceptable substitute search in certain situations. However, it is important to note that where the standard U.S. subclasses have substantially complete overlap within a Cross-Reference Art Collection subclass, cross-referencing from that U.S. subclass into the Cross-Reference Art Collection subclass has not been done, and a note appears in each of those subclasses indicating that cross-referencing is unnecessarily duplicative and that a complete search of the Cross-Reference Art Collection concept would have to include the noted U.S. subclass. For example, a U.S. patent cross-referenced into subclass 75
would not be placed into the cross-reference art collection 921, as the notes therein indicate.
NOTES TO THE CLASS DEFINITION
(1) Note. DEFINITION OF SINGLE-CRYSTAL*. The definition of single-crystal* for this class is set forth below in the Glossary below.
Twins*, oriented-crystals*, and superlattices* are included in this class because they are similar or identical to the more conventionally categorized epitaxy* and single-crystals*. Further, such materials are frequently used as though they are single-crystals*. The use of the term single-crystal* throughout this class will be taken to encompass twin*, superlattice*, epitaxy*, oriented-crystal*, or single-crystal*.
Both twins* and superlattices* are considered to be composed of layers of single-crystals* and therefore are classified where layered single-crystals* are provided for in the schedule.
(2) Note. KEYWORDS.
References directed to the following are deemed proper for Class 117 unless the disclosure reveals that the product is not single-crystal*:
crystal or seed pulling;
Verneuil method;
whisker growth;
superlattice*;
twin*;
oriented-crystal*;
epitaxy*; or epitaxial* deposition or growth.
(3) Note. INDICATIVE TERMINOLOGY.
The following criteria are intended to assist in the determination of whether placement is proper in this class.
(a) Positive indications include:
the use of one or more of the terms monolithic crystal, single crystal, isotropic crystal, monocrystal, or macro-crystal;
method or apparatus which produces a true single crystal; i.e., only one crystal;
method or apparatus which produces multiple single-crystals* simultaneously by virtue of multiple, purposeful seed crystals; and
the reference clearly focuses on the utility of a single-crystal* (e.g., optical or electrical device comprising one crystal, or a gemstone).
Class 117 is not the proper place for uncontrolled crystallization. When processing conditions may be controlled with an intent to encourage growth of a larger size crystal, this does not rise to the level of single-crystal* growth or apparatus for Class 117 if recovery involves merely selecting product crystals which are merely fortuitously large enough from the other product crystals. The following may be considered as indicating (but necessarily determining) that placement does not belong in Class 117.
(b) Negative indications include:
spontaneously nucleated crystallization; i.e., without seed crystal; crystallization which results in an indefinite number of crystals and/or in an indefinite distribution of crystal sizes;
crystallization for the stated purpose of recovery and/or purification of the material, particularly when an intended use doesn't depend upon a single-crystal* property; e.g., crystallization of salt or sugar to achieve purification or recovery;
the use of the term bulk crystals or polycrystalline; and
the reference focuses on bulk uses; e.g., abrasives.
NB: The term bulk crystal is used in some technologies to mean single-crystal* while the term bulk crystals is used in some technologies to mean numerous purified crystals, usually from material recovery operations.
(4) Note. PERFECTING OPERATIONS COMBINED WITH GROWTH.
This class provides for single-crystal* growth and apparatus combined with perfecting operations and means, unless such combination is specifically provided for elsewhere.
Perfecting operations are as defined herein or are operations which are merely broadly or nominally claimed so as not to be a basis for classification in an art class.
Special class lines affecting placement of single-crystal*
growth combined with perfecting steps exist with the metallurgy arts (Class 148 and Class 164), and with the semiconductor art of Class 438, as noted herein below. As a result of these special class lines, certain operations combined with single-crystal* growing which are otherwise perfecting for this class are provided for and placed outside of Class 117 (i.e., if the single-crystal* is a non-semiconductor metal* or is a Class 438-type semiconductor).
Determination of whether a step or operation is perfecting focuses on its contribution to the forming of the single-crystal* product and on the single-crystal* product itself. Operations are categorized hereinbelow as (a) simultaneous, (b) prior, or (c) subsequent.
(a) Simultaneous. Simultaneous operations are those performed on the growing single-crystal*. All simultaneous operations performed upon the growing single-crystal* are considered perfecting and hence processes including simultaneous operations are located in this class. For example: doping the growing crystal while growing; plasma-enhanced CVD*; volatile constituent overpressure; growing while shaping (e.g., confined in a recess); etc.
However, Class 164 provides for processes and apparatus forming a non-semiconductor metal* single crystal in a mold.
(b) Prior.
Prior operations which are preparatory to the growth operation are perfecting. Preparatory operations may be enhancing of or necessary to the growth.
Examples of perfecting prior steps are: pretreatment or manipulation of a substrate* or seed* such as cleaning, polishing, shaping, etching, ablating, doping, diffusing, gettering, ion implanting, aligning, or positioning; preparation or manipulation of a precursor* such as (a) mixing together components of a liquid, or (b) deposition of other than single-crystal* material which is then subsequently grown to single-crystal* (e.g., amorphous material deposited) or subsequently recrystallized to single-crystal* (e.g., polycrystalline material deposited), or (c) working, shaping, and/or heat treating a solid precursor* which is subsequently grown to single-crystal* (e.g., in the solid phase); preparation, pretreatment, or manipulation of a base* if such is necessary to successful growth (e.g., to create the necessary substrate* for epitaxy*); pretreating a substrate* or seed* by preparing a non-seeding mask (e.g., patterning) directly on a substrate* or seed* (this may include several steps, such as coating followed by selective etching); pretreating a substrate* or seed* by etching a region thereof (e.g., making a groove); combinations of perfecting steps.
Examples of claimed prior steps proper for Class 438 when combined with single-crystal* growth are: nonuniform material removal of a substrate* or base* in order to impart Class 438-type semiconductor device structure or region (i.e., other than to uniformly clean or "polish" the substrate) to a subsequently formed single-crystal* (e.g., etching or ablating to form a recess, groove, rib, mesa, ridge, strip, stripe, terrace, trench, trough, etc., see U.S. Patent No. 4,383,883), except that removal of non-seed material (e.g., a mask) in order to expose a seed* material (i.e., to expose a substrate*) followed by material deposition and single-crystal* growth seeded by the exposed substrate* is placed in Class 117 (e.g., epitaxial* layer overgrowth); acting to alter the composition of a substrate* or a non-seed material so as to provide a Class 438-type semiconductor device structure or region, even if performed uniformly or even if such is also necessary to prepare the substrate* to achieve the subsequent crystal growth (e.g., doping by ion implanting, diffusing or fusing, gettering); broad or nominal claimed step of forming a Class 438-type semiconductor device region or structure in a substrate*. Note, repeatedly growing single-crystal* on single-crystal* is a Class 117 process.
(c) Subsequent.
Subsequent operations are perfecting usually only if they do not modify the physical shape or the single-crystallinity of the grown single-crystal*.
Growth combined with subsequent shaping operations are usually beyond perfecting and are usually proper for classes providing for combination operations such as Class 29, Class 438, Class 264, and Class 156.
Subsequent steps which are considered perfecting are typically recovery steps or the operation recited merely broadly or nominally so as not to afford a basis of classification in an art class. In addition, heat treatment and impurity content modifying (e.g., doping or implanting or diffusing or gettering) are designated perfecting operations in this class.
Examples of perfecting subsequent operations are: cleaning; removing "flashing" (the unintentional or extraneous material); washing; drying; removing a substrate* or a base*; removing a mask; separating from a substrate* or a base*; removing from a reaction vessel; uniformly etching or grinding (e.g., polishing or cleaning); impurity content modifying (e.g., doping, implanting, diffusing, gettering); and heat treating (e.g., annealing, tempering). Examples of subsequent operations which are beyond perfecting when combined with single crystal growth are: nonuniform material removal (such as etching or ablating) to provide structure in the single-crystal* (e.g., groove, rib, mesa,
ridge, strip, stripe, terrace, recess, trench, trough); coating with other than single-crystal* material; bombardment to produce an induced nuclear reaction or transmutation (see Class 376, subclasses 156+).
Examples of claimed subsequent perfecting operations proper for Class 438 when acting upon or forming a Class 438-type semiconductor device and when combined with single-crystal* growth are: nonuniform material removal of a substrate or non-seed base in order to impact structure to a previously formed single crystal component of the semiconductor substrate, such structure intended to permit the utilization of the electrical characteristics of the semiconductive regions thereof (e.g., etching or ablating to form a recess, groove, rib, mesa, ridge, strip, stripe, terrace, trench, trough, see U.S. Patent No. 4,383,883); composition modifying, whether uniformly or otherwise (e.g., doping, gettering); heat treatment (except merely a specified cooling schedule, which is proper for Class 117, subclass 3); and a broad or nominally recited step of forming a Class 438-type semiconductor electrical device or device structure or device region.
Class 148 provides for single-crystal* growing when combined with a subsequent heat treatment (which herein includes controlled cooling) step when the purpose of the heat treatment (or controlled cooling) is to modify the internal physical structure or chemical property of a metal, alloy, or intermetallic material. Examples of claimed sebsequent operations proper for Class 148 even when combined with single-crystal* growth are solutionizing, homogenizing, and precipitation hardening.
(5) Note. CHEMICAL AND PHYSICAL REACTIONS.
Class 117 provides for single-crystal* growth and apparatus without regard to whether such growth and apparatus involves a chemical reaction* or a physical reaction or any combination thereof.
(6) Note. ZONE MELTING (E.G., ZMR*).
Processes and apparatus directed to moving zone melting or zone melt refining or zone leveling are assumed not to result in a single-crystal*, absent a recitation that a single-crystal* is formed.
However, where it is clear by disclosure that the usefulness of the intended product of the claimed process or apparatus relies upon a single-crystal* property (e.g., semiconductor for electronic devices), then it is appropriate to infer that the product is a single-crystal* even in the absence of an explicit statement.
(7) Note. SINGLE-CRYSTAL* MATRIX MATERIALS; NON-HOMOGENEOUS, NON-ISOTROPIC, OR IMPURE SINGLE-CRYSTALS*.
Class 117 takes processes and apparatus for making a single-crystal* having an impurity or foreign component therein so long as the single-crystal* forms a continuous matrix. Examples of materials found within single-crystals* are: (a) electronic property affecting impurity (e.g., semiconductor dopant*); (b) optical property affecting component (e.g., solid needle crystals of titanium (IV) oxide within beryl matrix); and (c) a processing remnant such as a processing aide (e.g., graphite string used in string-stabilized web crystal).
(8) Note. TREATMENT OF SINGLE-CRYSTALS*.
Single-crystal* treatment, not combined with a step of growing a single-crystal*, is not provided for in Class 117.
Per se doping is proper for (a) Class 427 or (b) either Class 252 or Class 501 if a nonsignificant coating step makes a composition or (c) Class 438, if therein provided for.
Per se heat treatment of Class 438-type semiconductor material, including single-crystal* material, is provided for in Class 438. (However, note that application of heat to a polycrystalline or amorphous material to grow a single-crystal* is proper for Class 117.)
Per se heat treatment of non-semiconductor metal* to modify or maintain the internal physical structure (e.g., microstructure) or chemical properties of non-semiconductor metal* is proper for Class 148. Note, however, that solid phase single-crystal* growing (i.e., heat treatment to recrystallize) of all materials, including the non-semiconductor metals*, is proper for Class 117.
Per se heat treatment of non-semiconductor, non-metal*, preformed, shaped, or solid article for the purpose of modifying or controlling the chemical or physical properties or characteristics of the article is proper for Class 264, subclasses 345+.
A. NOTES APPLICABLE ONLY TO PROCESSES OF THIS CLASS
A reference directed to process(es) which forms a single-crystal* species and which forms any one or combination of the species of an amorphous material or a polycrystalline material or multiple (non-single-crystal*) crystals (a) is proper for placement of the original where the most comprehensive embodiment is proper and (b) where there are equally comprehensive claims, is proper for placement of the original in Class 117, if single-crystal* embodiment is in any claim, singly or listed, or if only generic claims are presented and single-crystal* embodiment is disclosed.
(2) Note. Variously Classified Coating Operations. A reference directed to coating process(es) which forms a single-crystal* coating species and which forms either or both of the species of an amorphous coating or a polycrystalline coating (a) is proper for placement of the original where the most comprehensive embodiment is proper and (b) where there are equally comprehensive claims, is classified using a genus-species rule as follows. A reference with coating process(es) which forms a single-crystal* coating as the solely claimed or disclosed species is proper for placement of the original in Class 117. A reference with generic claim(s) and plural claimed species or plural disclosed species is proper for placement of the original to Class 427 or Class 438, as appropriate.
B. NOTES APPLICABLE ONLY TO APPARATUS OF THIS CLASS
(1) Note. Coating Versus Non-Coating Apparatus.
Single-crystal* growth requires layering deposition of molecule upon molecule. However, in the case of apparatus for single-crystal* growth, a distinction is made between that used for a method of coating and that used for a method of non-coating.
Where the grown material is intended to mimic the shape of the substrate* or base*, then the grown material is a coating (often the substrate* or base* remains as a significant or integral part of the product in use), and the apparatus effective therefor is classified in Class 118, Class 204, or Class 422. On the other hand, when the material deposition occurs so as to produce a product substantially independent of or far removed of the initial substrate* or base*, then the process is non-coating single-crystal* growth (often the substrate* or base* is not significant to or an integral part of the product in use), and the apparatus effective therefor is classified in Class 117.
Generally, Class 118 takes the apparatus for epitaxial* single-crystal* growth, while Class 117 takes most other single-crystal* growing apparatus.
(2) Note. Subcombination Apparatus.
Subcombinations having specific applications are placed with that specific application unless there is an art class providing for it.
(3) Note. Apparatus With Multiple Uses.
A reference having equally comprehensive claims to apparatus for multiple uses, or multiply disclosed uses and only generic claims (for example for making single-crystal* material or for making polycrystal material), is properly placed in Class 117 for the original and is cross-referenced
to the other appropriate apparatus class for the other embodiments.
Further lines with other classes are found in References To Other Classes, below. They are identified as (1) Lines With Process Classes; (2) Lines with Article, Material, Composition, Device, And Product Classes; (3) Lines With Apparatus Classes LINES WITH OTHER CLASSES
A. LINES WITH PROCESS CLASSES
See Notes, in section I, C and D, above and References to Other Classes, below.
B. SELECTED NOTES TO ARTICLE, MATERIAL, COMPOSITION, DEVICE,AND PRODUCT CLASSES
Class 117 does not provide for the products of its processes or apparatus. The following is not represented as a complete listing of all possible locations for such products, but may be useful as a guide or starting point for locating them. See References to Other Classes, below.
C. LINES WITH APPARATUS CLASSES
See Notes, in section I, C and E, above, and References to Other Classes, below.
REFERENCES TO OTHER CLASSES
SEE OR SEARCH CLASS
23, Chemistry: Physical Processes, for crystallization of inorganic compounds or non-metal* elements with no intent to obtain a single-crystal* product and having no significant shaping. Placement of the original, when both Class 117 and Class 23 species are claimed or where such are disclosed but only generic claims are present, is Class 117. (Process Class, Also see Notes, in section I, C and D, above.) (A., Lines With Process Classes)
29, Metal Working, for processes which include diverse operations and which include a step of single-crystal* growth when making the specified articles enumerated in that part of the Class 29 schedule which precedes
592, Processes of Mechanical Manufacture. Additionally, Class 29 takes processes which include diverse operations and which include a step of single-crystal* growth combined with (a) specific metal shaping steps or (b) mechanical joining either broad or specific. Class 117 takes multistep processes which include a step of single-crystal* growth combined with (a) broad or nominally claimed metal shaping steps or (b) assembling the precursors* of forming the single-crystal*. See subclasses 592.1+ for processes of mechanical manufacture of electrical devices not classified elsewhere. (A., Lines With Process Classes)
29, Metal Working, takes apparatus which practice diverse operations and which include a means of single-crystal* growth when making the specified articles enumerated in that part of the Class 29 schedule which precedes
592, Processes of Mechanical Manufacture. For example, see subclass 25.35 for apparatus for manufacturing piezoelectric crystal devices by means comprising single-crystal* forming and additional manufacturing means. Additionally, Class 29 takes apparatus which practice diverse operations and which include a means of single-crystal* growth combined with (a) specific metal shaping means or (b) mechanical joining means either broad or specific. Class 117 takes apparatus which include a means of single-crystal* growth combined with (a) broad or nominally claimed metal shaping means or (b) means for assembling the precursors* of forming the single-crystal*. (C., Lines With Apparatus Classes.)
34, Drying and Gas or Vapor Contact With Solids, appropriate subclasses for cooling, treating, and drying processes not in combination with single-crystal* formation; e.g., solidification of bulk material. For further elucidation of what Class 34 takes, see (2) Note therein. Class 117 takes drying and gas or vapor contact of single-crystal* as a perfecting operation; i.e., combined with single-crystal* growth. (A., Lines With Process Classes)
34, Drying and Gas or Vapor Contact With Solids, for cooling, treating, or drying apparatus, not combined with single-crystal* forming means. See Class 34 definition for comprehensive statement of its relationship with other classes. (C., Lines With Apparatus Classes.)
62, Refrigeration, appropriate subclasses for processes of other than single-crystal* growing which include a Class 62 cooling step. (A., Lines With Process Classes)
62, Refrigeration, for apparatus for removing heat from a substance which may cause crystallization and not combined with single-crystal* forming means. (C., Lines With Apparatus Classes.)
63, Jewelry,
32, for a gem or a stone intended to be worn by a person as an ornament. (B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
65, Glass Manufacturing, for processes of making glass. Fused quartz is considered glass. (A., Lines With Process Classes)
65, Glass Manufacturing, for glass making apparatus, especially 187+, and 193+, for means for pulling glass from a melt. (C., Lines With Apparatus Classes.)
75, Specialized Metallurgical Processes, Compositions for Use Therein, Consolidated Metal Powder Compositions, etc.,
10.11, for zone melting or refining and for fractional crystallization of metals or alloys wherein no single-crystal* is produced. If both single-crystal* and polycrystal formation are claimed, or both are disclosed but only generic claims are present, the original is proper for Class 117. See subclasses 331+ for forming metal powders from a melt or liquid without a shaping surface; e.g., liquid comminuting. (A., Lines With Process Classes)
118, Coating Apparatus, for apparatus for applying or obtaining a coating on a substrate (e.g., epitaxy*) and for apparatus not provided for elsewhere for treating the substrate (or base or work) or to subsequently treat the coating. See especially
400+, for liquid phase epitaxy* and subclasses 715+ for vapor phase epitaxy*. Apparatus for the non-coating (e.g., non-epitaxy*) single-crystal* growth is proper for Class 117. (C., Lines With Apparatus Classes.)
122, Liquid Heaters and Vaporizers, for apparatus for heating liquids which have a closed liquid heating chamber of generally disclosed utility and not combined with single-crystal* forming means. (C., Lines With Apparatus Classes.)
125, Stone Working, for processes of acting upon stone and stone-like material previously removed from its native position in the earth. (A., Lines With Process Classes)
126, Stoves and Furnaces, for apparatus for heating liquids which have an open liquid heating chamber of generally disclosed utility and not combined with single-crystal* forming means. (C., Lines With Apparatus Classes.)
127, Sugar, Starch, and Carbohydrates, appropriate subclasses for processes of recovery or treatment of class named materials which are not single-crystal*. (A., Lines With Process Classes)
127, Sugar, Starch, and Carbohydrates, appropriate subclasses for products of the processes of recovery or treatment of class named materials.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
127, Sugar, Starch, and Carbohydrates,
15+, and 17+ for apparatus for bulk crystallizing and treatment of bulk crystals of the class-defined materials. (C., Lines With Apparatus Classes.)
134, Cleaning and Liquid Contact With Solids, for apparatus for cleaning and for miscellaneous contact of liquids with solids in general, including such with single-crystal*, and not combined with single-crystal* forming means. (C., Lines With Apparatus Classes.)
136, Batteries: Thermoelectric and Photoelectric,
200+, for thermoelectric devices, subclasses 203+ for Peltier* thermoelectric effect devices, and subclasses 243+ for solar cell devices.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
148, Metal Treatment, appropriate subclasses for (a) the class provided for per se processes of non-semiconductor metal* treating or (b) single-crystal* growth of metal, alloy, or intermetallic material combined with a subsequent step of heat treatment (which herein includes controlled cooling) when the purpose of the heat treatment (or controlled cooling) is to modify the internal physical structure or chemical property of a metal, alloy, or intermetallic material. When the subsequent heat treatment (or controlled cooling) merely operates on the single-crystallinity, such as stress or strain annealing or to remove point defects, the combined process is proper for Class 117; when the subsequent heat treatment (or controlled cooling) operates to effect significant metal, alloy, or intermetallic heat treatment (or controlled cooling) purposes, such as solutionizing, homogenizing, or precipitation hardening, then the combined process is proper for Class 148. Class 117 provides for simultaneous or prior perfecting operations combined wiht single-crystal growing. See Class 117 definition, section C, (4) Note, for discussion of perfecting operations. (A., Lines With Process Classes)
148, Metal Treatment,
33+, for p/n junction semiconductor stock material (including superlattice materials), subclasses 400+ for metal* stock material, and subclass 404 for directionally solidified metal* stock material.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
159, Concentrating Evaporators,
47.1+, for processes of crystallization without significant chemical changes and in which single-crystal* growth is not intended. (A., Lines With Process Classes)
159, Concentrating Evaporators,
33, and subclass 45 for concentrating evaporators with means for collecting (bulk) crystals. (C., Lines With Apparatus Classes.)
164, Metal Founding,
122.1+, for simultaneously shaping (i.e., in a mold) and solidifying to form non-semiconductor metal* directionally solidified material or single-crystal*. See subclasses 48+, 250.1+, and 469 and Digest 5 for the use of high energy radiation to melt a metal* when not combined with growing a single-crystal*. (A., Lines With Process Classes)
164, Metal Founding, appropriate subclasses for apparatus for dynamic metal* molding or for treating of metal* in a mold, including apparatus which grows metal* single-crystal*. (C., Lines With Apparatus Classes.)
165, Heat Exchange, for apparatus for heating and cooling the same material, including single-crystal*, when not combined with single-crystal* forming means. (C., Lines With Apparatus Classes.)
196, Mineral Oils: Apparatus,
14.5, for dewaxing apparatus of mineral oils by solidification or crystallization. (C., Lines With Apparatus Classes.)
203, Distillation: Processes, Separatory,
48, for processes of distillation combined with crystallization (bulk). (A., Lines With Process Classes)
204, Chemistry: Electric and Wave Energy, for processes of forming a single crystal by a method set forth in that class definition as restricted in the Class 204 class definition, (5) Note, and the Class 204,
157.15, (9) Note. Thus, Class 204 is proper for single-crystal* growth processes which involve a stated chemical reaction and glow discharge, plasma torch, electrolysis, electrophoresis, sputtering, or vacuum arc discharge. (A., Lines With Process Classes)
204, Chemistry: Electrical and Wave Energy, for apparatus for forming single crystal by a Class 204 method which involves a stated chemical reaction, but with exceptions noted in the class definition at (C) and in (5) Note; see Class 204,
157.15, (9) Note. (C., Lines With Apparatus Classes.) 210, Liquid Purification or Separation, appropriate subclasses for processes which include crystallization, other than single-crystal* growth, when such is a by-product of a process which occurs simultaneously with a Class 210-defined process which is the primary purpose. (A., Lines With Process Classes)
210, Liquid Purification or Separation, for apparatus in which recovery of a crystallized material is a by-product of
a Class 210-defined process which is the primary purpose. Since placement is according to disclosed intent, appropriate cross-referencing is usually required. (C., Lines With Apparatus Classes.)
219, Electric Heating, for processes using high energy radiation to melt, absent the growing of a single-crystal*. (A., Lines With Process Classes)
219, Electric Heating, for electrical heating devices of generally disclosed utility and not combined with single-crystal* forming means. (C., Lines With Apparatus Classes.)
226, Advancing Material of Indeterminate Length, appropriate subclasses for processes of handling single crystals of indeterminate length (e.g., fiber) and not combined with single-crystal* forming means. (A., Lines With Process Classes)
226, Advancing Material of Indeterminate Length, appropriate subclasses for apparatus for handling single crystals of indeterminate length (e.g., fiber) and not combined with single-crystal* forming means. (C., Lines With Apparatus Classes.)
249, Static Molds, appropriate subclasses for static mold of fluent material not combined with a diverse art device such as single-crystal* forming means. (C., Lines With Apparatus Classes.)
252, Compositions, appropriate subclasses for processes of making compositions of the class, unless by a process provided for elsewhere. See
62.3+, for processes of making a composition suitable for a barrier layer device (e.g., by doping without a claimed step of crystal growing); subclasses 500+ for making electrically conductive or emissive compositions; subclasses 582+ for making non-linear optical compositions; subclasses 301.16+, 301.36, or 301.4+ for making coherent light generating compositions; and subclasses 299.01+ for making liquid crystal compositions. (A., Lines With Process Classes)
252, Compositions, for class provided for compositions, which may be single-crystal*, especially:
62.3+, for barrier layer device compositions such as p-type and n-type semiconductor materials; subclass 62.9 for piezoelectric compositions; subclasses 301.16+, 301.36, and 301.4+ for light emitting compositions (e.g., fluorescent, phosphorescent, or coherent (laser)); subclasses 500+ for electrically conductive or emissive compositions; subclasses 582+ for non-linear optical compositions; and subclasses 299.01+ for liquid crystal compositions.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
257, Active Solid-State Devices (e.g., Transistors, Solid-State Diodes), for semiconductor devices such as diodes, transistors, and thyristors.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
264, Plastic and Nonmetallic Article Shaping or Treating: Processes, for per se processes of shaping or treating non-glass, non-metal* single-crystal*, except as provided for in Class 437, and for processes of single-crystal* forming of non-semiconductor, non-metal* material combined with a step proper for Class 264 and which is not a Class 117 perfecting step (see the Class 117 definition, section I, C, (4) Note). See
5+, for forming non-glass, non-metal* powders from a melt or liquid without a shaping surface; e.g., liquid comminuting. Class 117 takes (a) single-crystal* growing simultaneous with shaping (except molding of non-semiconductor metal* which is placed in Class 164, subclasses 122.1+) or (b) single-crystal* forming of all types of materials, including organic or inorganic (non-metal* or metal*), combined with a broad or nominally recited shaping or treating step. See subclasses 340+ for the per se treating of a preformed, shaped, or solid article, which may be a single-crystal*, wherein the chemical or physical property or characteristic is modified or controlled, and see subclasses 345+ thereunder where such treatment is heat treating the article. (A., Lines With Process Classes)
266, Metallurgical Apparatus, appropriate subclasses for apparatus for refining, purifying, or otherwise treating molten or liquified metal* or for melting metal*, not provided for elsewhere.
269, Work Holders, e.g.,
46, for workholders not provided for in other art classes. Class 117 takes its own workholders. (C., Lines With Apparatus Classes.)
310, Electrical Generator or Motor Structure,
311+, for an inorganic piezoelectric structure when shaped to claimed configuration, where the configuration is disclosed as being significant to the piezoelectric property of the material (e.g., plate).(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
356, Optics: Measuring and Testing,
30+, for processes of optical measuring or testing of a crystal or a gem. (A., Lines With Process Classes)
356, Optics: Measuring and Testing,
30+, for apparatus for optical measuring or testing of crystal or gem. (C., Lines With Apparatus Classes.)
359, Optics: Systems (Including Communication) and Elements, for optical elements and optical systems not elsewhere classified.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
366, Agitating, appropriate subclasses for agitating apparatus not intended for chemical reaction and not combined with single-crystal* forming means. (C., Lines With Apparatus Classes.)
372, Coherent Light Generators, appropriate subclasses for art named devices (e.g., lasers), especially
43+, for semiconductor lasers.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
373, Industrial Electric Heating Furnaces, appropriate subclasses for apparatus having a specific electrical heating structure and of generally disclosed utility and for heating a material, especially
17, for apparatus for zone melting by electron beam furnace and subclass 139 for apparatus for zone melting by induction heating. Class 117 takes apparatus claimed or solely disclosed for single-crystal* growing. (C., Lines With Apparatus Classes.)
376, Induced Nuclear Reactions: Processes, Systems, and Elements, especially
156+, for processes, either per se or combined with single-crystal* growing, of acting on a single-crystal* which involves bombardment (e.g., irradiation, to produce an induced nuclear reaction or transformation), especially subclass 183 for doping a semiconductor material. (A., Lines With Process Classes)
376, Induced Nuclear Reactions: Processes, Systems, and Elements, appropriate subclasses for apparatus for carrying out nuclear reactions which may act on a single-crystal*; e.g., irradiation to perform nuclear transformation (e.g., doping of a semiconductor material). (C., Lines With Apparatus Classes.)
385, Optical Waveguides, for passive optical elements effecting a deviation of light rays or a modification in the character or properties of the light, especially 129+, for planar optical waveguides.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
419, Powder Metallurgy Processes, for processes of forming single-crystals* by Class 419 methods.
420, Alloys or Metallic Compositions, for methods of making metals and metallic compositions, other than single-crystal*. (A., Lines With Process Classes)
420, Alloys or Metallic Compositions, for metal*, alloy, or intermetallic compositions which may be single-crystal*.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
422, Chemical Apparatus and Process Disinfecting, Deodorizing, Preserving, or Sterilizing,
129+, for apparatus for crystallizing material other than single-crystal*, not provided for elsewhere, and in which chemical reaction(s) is(are) provided for; subclasses 186+ for apparatus for forming single-crystal* by a method of Class 204, subclasses 157.15+; subclasses 245.1+ for apparatus for crystallizing material other than single-crystal*, not provided for elsewhere, in which only physical process(es) is(are) provided for; and in all cases such apparatus not intended for acting upon glass or metal*, or for shaping an article. (C., Lines With Apparatus Classes.)
423, Chemistry of Inorganic Compounds, for processes of producing or separating by a chemical reaction an inorganic compound or non-metal* element, which may have crystalline form, and where there is no intent to obtain a single-crystal* product. Note, although Class 117 is proper for original placement of single-crystal* diamond making, a mandatory search is found in Class 423,
446, which is the locus for all diamond making and products (unless a coating), whether or not a chemical reaction is involved. (A., Lines With Process Classes)
423, Chemistry of Inorganic Compounds, for inorganic compounds or nonmetal* elements, single-crystal* or otherwise, especially where shape, structure, or device is not claimed.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
425, Plastic Article or Earthenware Shaping or Treating: Apparatus,
6+, for apparatus making non-glass, non-metal* powders, which may be crystals, from liquid by means dividing or comminuting and allowing the liquid to solidify while in particulate form of a desired size or shape but with no shaping surface; subclass 77 for ultra-high-pressure generating apparatus other than for single-crystal* forming; subclass 222 for tumbling type agglomerating apparatus; and appropriate subclasses for dynamic molding apparatus for other than glass. 427, Coating Processes, appropriate subclasses for processes
of depositing a coating other than single-crystal* (e.g., polycrystalline or amorphous) on a substrate, except as specifically provided for elsewhere. (A., Lines With Process Classes)
428, Stock Material or Miscellaneous Articles, for structurally defined non-metal* single-crystal* products, and for non-structurally defined laminates comprising a single-crystal*, particularly
544+, for a metal* stock having contiguous metal* layers (e.g., where one or more layers may be single-crystal*).(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
430, Radiation Imagery Chemistry: Process, Composition, or Product Thereof, for processes which include a single-crystal* growth step combined with a non-perfecting (see Class 117 definition, section I, C, (4) Note) operation which is proper for this class. (A., Lines With Process Classes)
432, Heating, appropriate subclasses for apparatus of general utility for the generation of heat and its application to materials, not provided for elsewhere. (C., Lines With Apparatus Classes.)
438, Semiconductor Device Manufacturing: Process, appropriate subclasses for (a) per se treatments or operations acting on single-crystal* semiconductor material (e.g., heat treating, doping, etching, coating, etc.) not specifically provided for elsewhere or (b) growing a single-crystal* semiconductor material (i.e., a Class 117 step) combined with named diverse treatments or operations, including those noted in the Class 117 definition, section I, C, (4) Note. Where there are only generic claims and both Class 438 and Class 117 processes are disclosed, or where both Class 438 and Class 117 processes are claimed and the claims are equally comprehensive, the reference is originally placed in Class 438 and cross-referenced to Class 117. (A., Lines With Process Classes)
501, Compositions: Ceramic, for processes of making ceramic compositions not provided for in an art class and when there is no intention of growing single-crystal* ceramics. (A., Lines With Process Classes)
501, Compositions: Ceramic, for compositions of ceramic materials, especially
86, for synthetic single-crystal* ceramic composition of gem quality.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
505, Superconductor Technology: Apparatus, Material, Process, for all subject matter relating to high temperature (functioning above 30 degrees K) superconductor compositions,
materials, devices, and methods of making same. See 451, for zone melting or seed pulling processes which make superconductor precursors or products and see cross-reference art collection 729 for producing high temperature superconducting single crystal or single crystal film or single crystal layer. (A., Lines With Process Classes)
505, Superconductor Technology: Apparatus, Material, Process, for all subject matter relating to high temperature (functioning above 30 degrees K) superconductor compositions, materials, devices, and methods of making same, see
451, for processes of making superconducting precursor or product by zone melting or seed pulling and cross-reference art collection 729 for making high temperature superconducting single crystal or single crystal film or single crystal layer.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
520, 520-528, Synthetic Resins or Natural Rubbers, for processes of making materials of the class definition which are other than single-crystal*. (A., Lines With Process Classes)
520, 520-528, Synthetic Resins or Natural Rubbers, for materials of the class definition which may be single crystal.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
530, Chemistry: Natural Resins or Derivatives; Peptides or Proteins; Lignins or Reaction Products Thereof, for processes of making materials of the class definition which are other than single-crystal*. (A., Lines With Process Classes)
530, Chemistry: Natural Resins or Derivatives; Peptides or Proteins; Lignins or Reaction Products Thereof, for materials of the class definition which may be single crystal.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
532, 532-570, Organic Compounds, for processes of synthesizing organic compounds which are other than single-crystal*. (A., Lines With Process Classes)
532, 532-570, Organic Compounds, for materials of the class definition which may be single crystal.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
585, Chemistry of Hydrocarbon Compounds, for processes of making materials of the class definition which are other than single-crystal*. See
812+, for processes of purification, separation, or recovery of hydrocarbons by crystallization, other than single-crystal* forming. (A., Lines With Process Classes) 585, Chemistry of Hydrocarbon Compounds, for materials of the class definition which may be single crystal.(B., Selected Notes To Article, Material, Composition, Device, And Product Classes.)
GLOSSARY:
AMORPHOUS
Noncrystalline; having no molecular lattice structure; e.g., glass, liquid.
BASE
The surface upon which a coating is formed, except where a surface has been previously coated and a second coating is applied, in which case the initial surface is the base. Contrast with substrate*.
(From French; ball) A lump of material. In this class the term applies to the raw, single-crystal* product.
CBE
Chemical Beam Epitaxy*. CHALCEDONY
Microcrystalline form of quartz; usually milky or grayish in color.
CHEMICAL REACTION
For purposes of Class 117, chemical reaction is given a broad meaning. The following are included: metathesis; changing the water of hydration; forming intermetallic compounds from constituent elements or from alloys; forming compound semiconductor material from constituent elements; forming ions (ionization) or ionized plasma. Not included are: dissolution of a compound and solidification (e.g. crystallization) of the same compound; a change of phase (e.g., amorphous to single-crystal*); change of crystal phase or form (e.g., face centered cubic to body centered cubic).
CHRYSOBERYL
Beryllium aluminate; BeO[supscrpt].[end supscrpt]Al2O3; cat's eye; alexandrite; optionally with up to about 10 wt% chromium oxide and titanium oxide.
CORUNDUM
Natural aluminum oxide; Al2O3; sometimes with intended small amounts of cobalt (green), chromium (red; i.e., ruby), iron (yellow), magnesium, or silica; synthetic emery.
CRUCIBLE
A vessel for containing a molten material. The crucible may be of the same material as the molten material and may ultimately become molten.
CRYPTOCRYSTALLINE Microscopic crystalline structure, indistinguishable to the naked eye.
CRYSTAL BOUNDARY
The interface between a crystal and its surroundings; e.g., another crystal, air.
CSL
Coherent Superlattice.
CTSL
Coherent Tilted Superlattice.
CVD
Chemical Vapor Deposition. CVD may be employed to produce single-crystal*, polycrystal, or amorphous material. See also MOCVD.
CZ
Abbreviation for Czochralski. J. Czochralski was the Polish inventor of the basic single crystal pulling method (1918) bearing his name.
DIASPORE Al2O3[supscrpt].[end supscrpt]H2O; a natural hydrous aluminum oxide; HAlO2.
DOPANT
A desired material intentionally present in an amount insufficient to satisfy the lattice unit cell, which may be present interstitially or by occupying crystal lattice positions substitutionally.
DOPING
The process of introducing a dopant* into a material.
EDFFG
Edge-Defined Film-Fed Growth. Also abbreviated as EDFG and EFG.
EPITAXY
Formation of a single-crystal* on a substrate* (which acts as a seed*) or the product of such a process. Usually, the formed crystal bears a definite crystallos:graphic relationship to the substrate*. Typically, the term applies to coating or layer formation when the width and length are substantially larger than the height and when the substrate* remains as a significant or integral part of the product in use.
FERRITE SPINELS
MFe2O4, where M = divalent metal (or mixtures thereof) and having the cubic lattice structure. FET
Field Effect Transistor.
GARNET, SYNTHETIC
Term applied to crystals having the same complicated cubic structure as mineral garnets or beryl, but usually without the silicon; e.g., yttrium-iron, Y3Fe5O12. Other variations include substituting part of the yttrium and/or iron with valence-equivalent metals.
GETTERING
A process or operation that reduces or removes impurities or defects from a region either by complete removal (e.g., volatilization) or by transporting them to another region.
GGG
Gadolinium Gallium Garnet. Composite oxide compound Gd3Ga5O12. Useful as substrate in magnetic bubble domain memory and as man-made gemstones.
IMMEDIATE-PRECURSOR
The precursor immediately next to the growing single-crystal* and from which the single-crystal* forms or grows. Contrast with precursor*.
JUNCTION, SEMICONDUCTOR The region of transition between semiconduction regions of different electrical properties, usually between p-type and n-type materials, and usually a junction exhibits asymmetric conductivity.
LATTICE CONSTANT
Usually the edge length of a unit cell.
LEC
Liquid Encapsulated Czochralski (CZ*) method.
MBE
Molecular Beam Epitaxy*.
METAL
Element other than non-metal* (see non-metal*).
METAL, NON-SEMICONDUCTOR
See NON-SEMICONDUCTOR METAL.
MOCVD Metal-Organic CVD*. CVD in which a precursor* contains an organo-metallic compound. Also sometimes OMCVD.
MOMBE
Metal-Organic Molecular Beam Epitaxy*. MBE in which a precursor* contains an organo-metallic compound.
MOS FET
Metal Oxide Semiconductor Field Effect Transistor.
A metal* other than which has a disclosed semiconductor property or intended use. For example, a single-crystal* of germanium or indium antimonide would be inferred to be a semiconductor even though composed of a metal* because of its known semiconductor property.
NUTRIENT
The source material from which the single-crystal* deposits or grows. See also precursor*. ORIENTED-CRYSTAL
A material in which substantially all the crystal grains are oriented in a preferential way. Also called preferred-orientation polycrystalline material.
OMCVD
Metal-Organic CVD*.
PECVD
Plasma Enhanced CVD*.
PELTIER EFFECT
A thermoelectric effect wherein electric current between/through a solid/solid or a solid/liquid junction creates heating in one side and cooling in the other.
P/N JUNCTION
An interface formed by two semiconductor materials in which one contains a charge carrier which is an electron donor (n-type semiconductor) and the other contains a charge carrier which is an electron acceptor (p-type semiconductor).
PRECURSOR
Any part, or all, of the starting material from which a single-crystal* is grown. This may be a material which undergoes one or more chemical reactions* prior to the actual crystal growth step. Hence, the term is not limited to the compound or composition present just immediately prior to the growth of the single-crystal*. Contrast with immediate-precursor*. See also nutrient*. QUARTZ
SiO2; silicon dioxide; silica. Polycrystalline forms include agate, cat's eye, chalcedony, and jasper. Crystalline forms include amethyst, catalinite, citrine, rose quartz, and smoky quartz.
An interface formed by a semiconductor and a conductor.
SEED
A material, usually a single-crystal*, upon which a single-crystal* is grown. Seeded crystal growth proceeds by the alignment of atoms or molecules or clusters into a thermodynamically favored arrangement determined by the nature of the seed.
SEIGNETTE'S SALT See Rochelle salt.
SEMICONDUCTOR DEVICE
Used here to mean any article or structure comprised of semiconductor material, such as the optical waveguides of Class 385 or the electronic semiconductor devices of Class 438. The phrase is not determinative of proper classification; intended use frequently dictates proper classification.
SEMICONDUCTOR JUNCTION
See JUNCTION, SEMICONDUCTOR.
SINGLE-CRYSTAL
Solid phase material characterized by an absence of crystal boundaries and by a uniform atomic structural arrangement. However, in this class, the term includes material composed of twins*, superlattice*, epitaxy*, oriented-crystals*, or enlarged crystals (when the enlarged crystals are used as though they are a single-crystal or when the enlarged crystals are used individually as single-crystals).
SOI
Semiconductor On Insulator. A layered structure commonly found as the starting point for integrated circuit manufacture on silicon wafers.
SOS
Silicon On Sapphire. SPINEL
MAl2O4; rubicelle, ruby almandine, ruby balas. Also sometimes used generically to refer to a crystal having the cubic crystal lattice form.
SUBSTRATE
The surface upon which a coating is formed. In the case of single-crystal* growth, such as epitaxy*, the substrate is also a seed*. Contrast with base*.
SUPERLATTICE
A single-crystal*, usually composed of a semiconductor, having an internal structure of more than two layers, each layer having a composition different from the next adjacent layer. The term includes alternating layers of two compositions.
TWIN
(Twin plane) A polycrystalline material in which the adjoining lattices have a mirror-image symmetrical relationship.
VERNEUIL
A. Verneuil, French inventor of the crystal growth technique (1902) used for materials with a high melting point. The Verneuil method is typified by use of a high temperature heat source, such as a gas flame or plasma torch, into which powdered material is directed, whereupon it melts as or prior to its arrival to a thin film of melt on a seed crystal which is pulled away at an appropriate rate.
VFG
Vertical Freeze Gradient. Also VGF. VPE
Vapor Phase Epitaxy*.
WHISKER
A single-crystal* which is typically small diameter, elongate, and generally cylindrical.