Patent ID: 6506640
Filing Date: 2003-01-14
Classification: H01L

Abstract:
A method for manufacturing a semiconductor device comprising:ion implanting a first impurity of a first conductive type into a semiconductor substrate to form a retrograde impurity region having a first impurity concentration peak formed at a first depth below the top surface of the semiconductor substrate; ion implanting a second impurity of the first conductive type into the semiconductor substrate to form a shallow impurity region having a second impurity concentration peak at a second depth below the top surface, the second depth less than the first depth and the second impurity being different than the first impurity; further comprising ion implanting a third impurity of the first conductive type into the semiconductor substrate to form a deep impurity region having a third impurity concentration peak at a third depth below the top surface of the semiconductor substrate, the third depth greater than the first depth; and wherein the second and third impurities are boron and the first impurity is indium.