SEMICONDUCTOR DEVICE MANUFACTURING METHOD

摘要

A method of manufacturing a semiconductor device having a polycrystalline silicon layer (5) includes; a step of forming a mask layer (7) on the polycrystalline silicon layer (5); a step of forming a side wall (8) that is provided on a side face of the mask layer (7) and covers part of the polycrystalline silicon layer (6); a step of doping an impurity (52) into the polycrystalline silicon layer (5) by using at least one of the mask layer (7) and the side wall (8) as a mask; and a step of etching the polycrystalline silicon layer (5, 6) by using at least one of the mask layer (7) and the side wall (8) as a mask.