Patent ID: 7981746
Filing Date: 2011-07-19
Classification: H01L

Abstract:
1. A method for manufacturing a semiconductor device, the method comprising: forming a trench section in a semiconductor substrate; forming a tunnel insulating film that covers an inner surface of the trench section; forming a first conductive layer in the trench section so as to be in contact with the tunnel insulating film at a lower portion of the trench section, and so as to make the tunnel insulating film exposed at an upper portion of the trench section; forming a trap layer and a top insulating film sequentially on the first conductive layer, and in contact with the upper portion of the trench section; removing the trap layer and the top insulating film formed on the first conductive layer at a center portion of the trench section in the width direction; forming a second conductive layer on the first conductive layer at the center portion of the trench section in the width direction and on the top insulating film; and forming a gate electrode from the first conductive layer and the second conductive layer.