Patent ID: 7008828

Claim:
A method of manufacturing a semiconductor device, comprising: a first step of forming an insulating film on a semiconductor layer; a second step of forming a conductive layer on the insulating film; a third step of selectively etching the conductive layer, forming a conductive layer having a first tapered shape; a fourth step of doping a single conductivity type impurity element into the semiconductor layer, after completing the third step; a fifth step of selectively etching the conductive layer having the first tapered shape, forming a conductive layer having a second tapered shape; and a sixth step of doping a single conductivity type impurity element into the semiconductor layer overlapped with the second tapered shape, after completing the fifth step, wherein the concentration of the single conductivity type impurity element doped in the sixth step is lower than the concentration of the single conductivity type impurity element doped in the fourth step.