Patent ID: 7635622
Filing Date: 2009-12-22
Classification: H01L,Y10S

Abstract:
1. A method for manufacturing a semiconductor device comprising: forming a plurality of trenches on a first side of a semiconductor substrate, wherein the substrate has a first conductive type; forming a second conductive type semiconductor film in each trench so that the substrate between two adjacent trenches provides a first column, and the second conductive type semiconductor film in each trench provides a second column, wherein the first and second columns are alternately repeated along with a predetermined direction in parallel to the first side of the substrate; thinning a second side of the substrate, the second side being opposite to the first side; and increasing an impurity concentration of the first conductive type in a thinned second side of the substrate so that a first conductive type layer is provided, wherein the impurity concentration of the first conductive type layer is higher than an impurity concentration of the first column, and the first column provides a drift layer so that a vertical type first-conductive-type channel transistor is formed.