Method for producing single crystal SiC substrate and single crystal SiC substrate produced by the same

摘要

A single crystal SiC substrate is produced with low cost in which a polycrystalline SiC substrate with relatively low cost is used as a base material substrate where the single crystal SiC substrate has less strain, good crystallinity and large size. The method including a P-type ion introduction step for implanting P-type ions from a side of a surface Si layer 3 into an SOI substrate 1 in which the surface Si layer 3 and an embedded oxide layer 4 having a predetermined thickness are formed on an Si base material layer 2 to convert the embedded oxide layer 4 into a PSG layer 6 to lower a softening point, and an SiC forming step for heating the SOI substrate 1 having the PSG layer 6 formed therein in an atmosphere hydrocarbon-based gas to convert the surface Si layer 3 into SiC, and thereafter, cooling the resulting substrate to form a single crystal SiC layer 5 on a surface thereof.

主权项

1. A method for producing a GaN substrate, comprising:
a phosphorus ion introduction step for introducing phosphorus ions from a side of a surface Si layer into an SOI substrate in which the surface Si layer and an embedded oxide layer having a predetermined thickness are formed on an Si base material layer to convert the embedded oxide layer into an embedded glass layer to lower a softening point; and an SiC forming step for heating the SOI substrate having the embedded glass layer formed therein in an atmosphere of hydrocarbon-based gas to convert the surface Si layer into SiC, and thereafter, cooling the resulting substrate to form a single crystal SiC layer on a surface thereof, wherein the SiC forming step further comprises causing the embedded glass layer between the SiC layer and the Si base material layer to be transformed to cause slippage between the Si base material layer and the SiC layer, to accommodate a difference in shrinkage ratios between the SiC layer and the Si base material layer during performance of the method, heating and cooling to epitaxially grow the GaN layer on the single crystal SiC layer, and thereby causing the embedded glass layer between the SiC layer and the Si base material layer to be transformed to cause slippage between the Si base material layer and the SiC layer, to suppress warp of the entire SOI substrate with the formed single crystal SiC layer.