| 摘要 |
PURPOSE:To reduce the leakage currents of a semiconductor element, and to prevent the lowering of dielectric resistance by forming an electric element to an epitaxial crystal grown on a substrate in which the concentration of oxygen and carbon contained in a silicon crystal is limited. CONSTITUTION:When the concentration of oxygen in the silcon crystal is Oi and that of carbon Cs, a P type epitaxial layer 6 is formed on the surface of the P type silicon substrate 5 in Cs>=Oi>=14X10<17>cm<-3>, and an N type layer 7 is formed selectively to the surface of the P type epitaxial layer 6. Internal defects 8 are formed in the P type silicon substrate 5 in high density, but the P type epitaxial layer 6 is changed into a non-defective layer. The internal defects 8 are formed in high density because oxygen and carbon in Cs>=Oi>=14X10<17>cm<-3> are made contain in the P type silicon substrate 5, and no defect appear in the P type epitaxial layer 6 because oxygen is hardly contained in the layer 6. |
