| 摘要 |
PURPOSE:To improve quality of an epitaxial layer formed thereafter, by performing gaseous etching, whose amount is in excess of a projective range in ion implantation, before epitaxial growth. CONSTITUTION:After burial diffusion is performed on a semiconductor substrate by using ion implantation, gaseous etching whose amount is in excess of a projective range in the ion implantation, is performed with epitaxial growth being followed. For example, a Sb diffusion layer of desirable pattern is formed on a B-doped (111) P type wafer having resistivity of about 2 OMEGA cm, and then an oxidizing film of 6000 Angstrom in film thickness is formed as a mask for ion implantation on the surface. Successively, window opening is performed by normal lithography in a B ion implanting region, to form a thin oxidizing film of about 1000 Angstrom in thickness. Thereafter ion implantation is performed with acceleration energy of 70 Kev and dosage of 4X10<14> cm-<2>, and heat treatment at 1140 deg.C for 120 minutes is then performed under an atmosphere of N2 after the ion implantation so that recovery of defects and forced implantation B are caried on. After the whole oxidizing film is removed, gaseous etching is performed, and then an epitaxial layer having resistivity of 1OMEGAcm and thickness of 18 mum is made to grow by using SiCl4 as a source.
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