Silicon carbide seed crystal and method of manufacturing silicon carbide ingot
AssigneeGlobalWafers Co., Ltd.
InventorChing-Shan Lin
Life of this patent
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Abstract
The disclosure provides a silicon carbide seed crystal and a method of manufacturing a silicon carbide ingot. 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 and a basal plane dislocation density BPD2 of the carbon surface satisfies the following formula (1), a local thickness variation (LTV) of the silicon carbide seed crystal is 2.5 μm or less, and a stacking fault (SF) density of the silicon carbide seed crystal is 10 EA/cm2 or less: D=(BPD1−BPD2)/BPD1≤25% (1).
Claims10
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, a local thickness variation (LTV) of the silicon carbide seed crystal is 2.5 μm or less, and a stacking fault (SF) density of the silicon carbide seed crystal is 10 EA/cm2 or less:
- D=(BPD1−BPD2)/BPD1≤25% (1).
A method of manufacturing a silicon carbide ingot, comprising:
- disposing a silicon carbide seed crystal on a top of a crucible;
- disposing a silicon carbide based raw material in 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 the sublimed silicon carbide into a silicon carbide single crystal after being in contact with the silicon carbide seed crystal disposed on the top of the crucible;
- growing the silicon carbide single crystal continuously on the silicon carbide seed crystal to obtain silicon carbide ingots.
Dependencies are inferred from the claim text.