Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To obtain a back-surface electrode having excellent adhesion, by providing an ion implanted layer having higher concentration than a substrate but having the same conductive type on the back surface of the si substrate, and providing ohmic electrode directly thereon or on the exposed part of the surface layer. CONSTITUTION:The back surface of an N<+> collector 1 whose concentration is 5X10<18> atoms/cm<3> is ground, and P ions of 1X10<16> atoms/cm<3> are implanted at 100KeV. Then, a high-concentration layer 13, whose surface concentration is 8X 10<19> atoms/cm<3> is formed. Cr, Ni, Sn, and A gare sequentially evaporated on said layer 13 directly. Or they are evaporated on a high concentration layer 13' of 4X 10<20>/cm<3>, which is exposed by etching out the surface layer to the depth of about 0.2mu and an electrode 10 is obtained. In this constitution, the ohmic electrode which strongly adheres to the semiconductor substrate can be obtained, and the device having excellent characteristics is obtained. In the case of a P<+> substrate, the charactristics can be likewise improved by the implantation of B ions.

Inventors

• 👤 Masamitsu Yamauchi

Bibliographic Details