Method for producing field effect transistor

摘要

A method for producing a field effect transistor comprises: depositing a positive photoresist 2 a semiconductor substrate 1; imagewise exposing the positive photoresist 2; converting the positive photoresist 2 into a negative photoresist and developing to form a pattern 2a having an aperture 3; wet etching the semiconductor substrate 1 using the photoresist pattern 2a as a mask to form a first recess 4; further developing the photoresist pattern 2a to remove areas 21; using the photoresist pattern 2a with the increased overhanging portions as a mask, wet etching the semiconductor substrate 1 to increase the width of the first recess 4 and to form a second recess 4a; and depositing a gate metal to form a gate electrode 5 in the second recess 4a.