| 摘要 |
PURPOSE:To improve the carrier mobility of a semiconductor device formed on an insulating single crystal substrate by converting only the surface side in an active elemeent forming region, the entire surface and a semiconductor film in a load element forming region into amorphous region, and then recrystallizing it. CONSTITUTION:A single crystal Si vapor phase grown film 2 is grown on a sapphire single crystal substrate 1. Then, the film 2 is heated from the surface. Thereafter, a photoresist pattern 4 is formed on an active element region 3, with it as a mask Si ions are implanted only on a load element region 5, and an amorphous layer 6 is formed at the Si-sapphire boundary side of the region 6. Subsequently, a heat treatment is executed, and the layer 6 is formed into a recrystallized layer 7. Then, Si ions are implanted, to form the surface side of the film 2 into an amorphous layer 8. Thereafter, a heat teratment is performed to recrystallize the layer 8 to form a recrystallized layer 9. The crystallinity of only the surface side of the region 3 is improved by the above steps, an the entire crystallinity of the region 5 is improved. In this manner, the carrier mobility of a semiconductor device formed on the substrate 1 is improved, and the leakage current can be reduced more. |
