Patent ID: 7829374
Filing Date: 2010-11-09
Classification: H01L,Y10S

Abstract:
1. A method for producing a semiconductor device, comprising: a step (a) of preparing a silicon carbide semiconductor layer including an n-type impurity region and a p-type impurity region provided so as to be adjacent to each other; a step (b) of forming a stacking layer including a nickel layer and an aluminum layer on the p-type impurity region; a step (c) of thermally treating the stacking layer to form a p-type ohmic electrode containing an alloy of nickel, aluminum, silicon and carbon on the p-type impurity region; a step (d) of forming a titanium layer on at least a part of the n-type impurity region; and a step (e) of thermally treating the titanium layer to form an n-type ohmic electrode containing an alloy of titanium, silicon and carbon on the n-type impurity region, wherein the thermal treatment in steps (c) and (e) is performed at a temperature of 850° C. or higher and 1050° C. or lower, wherein the thermal treatment in steps (c) and (e) is performed in an atmosphere containing nitrogen gas or argon gas, wherein the step (b) includes: a step (b1) of forming a mask for exposing the p-type impurity region on the silicon carbide semiconductor layer; and a step (b2) of forming the stacking layer on the p-type impurity region and the mask; wherein the method comprises a step (f) of removing the stacking layer on the mask between the step (b2) and the step (d).