| 摘要 |
PURPOSE:To realize improvement of the device characteristics such as avoiding latch-up and alpha-ray soft error by forming a semiconductor element on one of main surfaces of a semiconductor substrate composed of a boron-doped P-type silicon substrate and silicon epitaxial films provided on both the sides of the P-type substrate. CONSTITUTION:A silicon epitaxial wafer is composed of a P<+>-type substrate 3 and a silicon epitaxial films 1 and 5 having a two places up higher specific resistivity than the P<+>-type substrate 3 and provided on both the sides of the P<+>-type substrate 3 and has misfit dislocations produced by the difference in lattice constant between the P<+>-type substrate 3 and the silicon epitaxial films 1 and 5. A device if formed on the silicon epitaxial wafer. With this constitution, sufficient latch-up and alpha-ray soft error strength can be provided and the yield of the device can be higher than the yield obtained from a prior art. |
