US PATENT SUBCLASS 117 / 78
.~.~ Precursor composition intentionally different from product (e.g., excess component, non-product forming component, dopant, non-stoichiometric precursor, solvent, flux)

Current as of: June, 1999
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117 /   HD   SINGLE-CRYSTAL, ORIENTED-CRYSTAL, AND EPITAXY GROWTH PROCESSES; NON-COATING APPARATUS THEREFOR

11  DF  PROCESSES OF GROWTH FROM LIQUID OR SUPERCRITICAL STATE {7}
73  DF  .~ Havin growth from molten state (e.g., solution melt) {6}
78.~.~ Precursor composition intentionally different from product (e.g., excess component, non-product forming component, dopant, non-stoichiometric precursor, solvent, flux) {2}
79  DF  .~.~.~> Unusable portion contains a metal atom (e.g., diamond or CBN growth in metal solvent)
80  DF  .~.~.~> Unusable portion contains an oxygen atom (e.g., oxide flux)

DEFINITION

Classification: 117/78

Precursor composition intentionally different from product (e.g., excess component, non-product forming component, dopant, non-stoichiometric precursor, solvent, flux):

(under subclass 73) Subject matter in which the precursor* composition is intentionally formulated different from the single-crystal* product grown therefrom which results in an unusable residual portion.

(1) Note. The unusable residual portion of the precursor* refers to the material that would be left if the desired single-crystal* product were grown as completely as possible. Examples of processes proper for placement in this subclass are: alumina single-crystal* grown from aluminum solvent or gallium arsenide single-crystal* grown from gallium solvent.

(2) Note. Since the distribution coefficient or segregation factor of dopants* is usually not unity, a process in which a doped crystal is formed is proper for placement here, except

when the reference states that the coefficient or the factor is unity.

(3) Note. Processes in which the liquid has undesired impurities which are rejected from the crystal at the precursor*-product interface are not proper for placement here.

(4) Note. Methods including evaporation of material in the precursor* composition, such as an excess component or a non-product forming component, are properly placed here.

SEE OR SEARCH THIS CLASS, SUBCLASS:

77, for processes in which the difference in compositions is due to or coupled to a gas or vapor state precursor* delivered to the melt during growth.