Claims
- 1. A method of forming tear-shaped semiconductor bodies of substantially uniform size with reduced grain boundaries therein, comprising:
- (a) introducing solid particles of semiconductor material into a capillary tube at the upper end of an elongated first chamber;
- (b) flowing inert gas into said first chamber to purge air therefrom and create an inert atmosphere therein;
- (c) heating said capillary tube to melt said semiconductor material;
- (d) forcing said molten semiconductor material through a nozzle in said capillary tube to form said melt into droplets at the upper end of said first chamber;
- (e) allowing said droplets to free fall through said inert gas atmosphere to cool to solidification as tear-shaped bodies;
- (f) collecting and introducing said tear-shaped bodies into a feed tube at the upper end of an elongated second chamber;
- (g) flowing inert gas into said second chamber to purge air therefrom and create an inert atmosphere therein;
- (h) heating an upper portion of said second chamber and said inert gas therein to form an upper zone having a temperature sufficient to melt said tear-shaped bodies passing therethrough;
- (i) establishing in a lower zone of said second chamber a temperature of said inert gas therein to solidify said molten tear-shaped bodies passing from said upper zone and through said lower zone;
- (j) releasing said solid tear-shaped bodies from said free tube to free fall through said second chamber upper zone to remelt said bodies at a predetermined rate, and then passing through said lower zone to resolidify said bodies at a slower rate to form tear-shaped semiconductor bodies having substantially uniform size and reduced grain boundaries therein; and
- (k) collecting said solidified tear-shaped semiconductor bodies.
- 2. The method of claim 1, where in step (a) the semiconductor material comprises a charge of solid material selected from the group consisting of silicon, germanium and galium arsenide.
- 3. The method of claim 1, where in steps (b) and (g) the inert gas comprises a gas selected from the group consisting of helium and argon.
- 4. The method of claim 1, where in steps (c) and (h) are carried out by induction heating.
- 5. The method of claim 1 where in step (d) the molten semiconductor material is forced through said nozzle in said capillary tube by application of inert gas pressure.
- 6. The tear-shaped semiconductor bodies formed by the method of claim 1.
- 7. A method of forming tear-shaped semiconductor bodies of substantially uniform size with reduced grain boundaries therein, comprising:
- (a) introducing solid particles of semiconductor material into a capillary tube at the upper end of an elongated chamber;
- (b) flowing inert gas into said chamber to purge air therefrom and create an inert atmosphere therein;
- (c) heating said capillary tube to melt said semiconductor material;
- (d) heating the upper end of said chamber and said inert gas therein to form a zone having a progressively decreasing temperature sufficient to allow gradual solidification of molten semiconductor bodies passing therethrough;
- (e) forcing said molten semiconductor material by application of inert gas pressure through a nozzle in said capillary tube to form said melt into droplets at the upper end of said chamber;
- (f) allowing said droplets to free fall through said chamber zone to gradually solidify therein and then continuing to fall on through the remainder of said chamber to cool into tear-shaped semiconductor bodies having substantially uniform size and reduced grain boundaries therein; and
- (g) collecting said solidified tear-shaped semiconductor bodies at the lower end of said chamber.
- 8. The method of claim 1, where in step (a) the semiconductor material comprises a material selected from the group consisting of silicon, germanium and galium arsenide.
- 9. The method of claim 7, where in steps (b) and (e) the gas comprises a gas selected from the group consisting of helium and argon.
- 10. The method of claim 7, where in step (c) is carried out by induction heating.
- 11. The tear-shaped semiconductor bodies formed by the method of claim 7.
Parent Case Info
This is a division of application Ser. No. 766,223 filed Feb. 7, 1977 now abandoned.
US Referenced Citations (3)
Divisions (1)
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Number |
Date |
Country |
Parent |
766223 |
Feb 1977 |
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