Silicon carbide seed crystal and method of manufacturing the same, and method of manufacturing silicon carbide ingot
AssigneeGlobalWafers Co., Ltd.
InventorChing-Shan Lin
Life of this patent
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Abstract
A silicon carbide seed crystal and method of manufacturing the same, and method of manufacturing silicon carbide ingot are provided. The silicon carbide seed crystal has a silicon surface and a carbon surface opposite to the silicon surface. A difference D between a basal plane dislocation density BPD1 of the silicon surface BPD1 and a basal plane dislocation density BPD2 of the carbon surface satisfies the following formula (1): D=(BPD1−BPD2)/BPD1≤25% (1).
Claims9
A silicon carbide seed crystal, wherein the silicon carbide seed crystal comprises a silicon surface and a carbon surface opposite to the silicon surface, wherein a difference D between a basal plane dislocation density BPD1 of the silicon surface and a basal plane dislocation density BPD2 of the carbon surface satisfies a formula (1) as follows:
- D=(BPD1−BPD2)/BPD1≤25% (1).
A method of manufacturing silicon carbide seed crystals, comprising:
- disposing a silicon carbide based raw material in a crucible;
- disposing a silicon carbide seed crystal on a top of the crucible;
- heating the silicon carbide based raw material to form a thermal field in the crucible so that the silicon carbide based raw material is sublimated in the thermal field of the crucible, wherein a radial temperature gradient of the thermal field in the crucible is greater than or equal to 5° C./cm and less than or equal to 50° C./cm;
- growing a silicon carbide single crystal from the sublimed silicon carbide after being in contact with the seed crystal disposed on the top of the crucible;
- and
- growing the silicon carbide single crystal on the seed crystal continuously to obtain silicon carbide ingots;
- wherein the silicon carbide seed crystal located on the top of the crucible is a first crystal, the silicon carbide ingot obtained by the growth of the first seed crystal and processed to satisfy D≤25% is a second seed crystal, and a method of manufacturing the second seed crystal further comprises:
- disposing the second seed crystal on a top of a crucible to grow a silicon carbide single crystal on the second seed crystal to grow an Nth silicon carbide ingot;
- and
- reusing the second seed crystal to grow an N+1th silicon carbide ingot on the second seed crystal.
Dependencies are inferred from the claim text.