| 摘要 |
When producing an SOS substrate by growing a silicon layer on a sapphire substrate, or when producing an SOI substrate by depositing an oxide layer or a fluoride layer, as an intermediate layer, on a silicon substrate, and growing a silicon layer on the deposited layer, (A) after growth of the silicon layer, heat treatment is performed in an oxidizing atmosphere to oxidize a part of a surface side of the silicon layer, and the resulting silicon oxide layer is removed by etching with hydrofluoric acid. (B) With this silicon layer as a seed layer, a silicon layer is regrown homoepitaxially thereon. When producing an SOS substrate by growing a silicon layer on a sapphire substrate, or when producing an SOI substrate by depositing an oxide layer or a fluoride layer, as an intermediate layer, on a silicon substrate, and growing a silicon layer on the deposited layer, (C) after growth of the silicon layer, the silicon layer is heated in a hydrogen atmosphere; or (D) while the silicon layer is being grown, its growth is suspended, and the silicon layer is heat treated in a hydrogen atmosphere to improve the surface flatness and crystallinity of the silicon layer, whereafter epitaxial growth of the silicon layer is performed again. Thus, a highly crystalline, highly oriented SOI substrate with few defects and minimal surface roughness is obtained. The formation of a semiconductor device with the use of this SOI substrate with few defects, high crystallinity and high orientation, and minimal surface roughness results in the acquisition of a semiconductor device with excellent device performance, such as high speed, low flicker noise, high drain breakdown voltage, and high ESD. <IMAGE> |
