Patent ID: 7608490

Claim:
A manufacturing method of a semiconductor device, comprising: crystallizing a semiconductor layer with a laser selected from the group consisting of a continuous wave laser and a pulsed laser with a repetition rate of 10 MHz to 100 GHz; forming a first insulating layer on the semiconductor layer after crystallizing the semiconductor layer by oxidation treatment with the use of oxygen radicals produced by plasma with an electron temperature of 3 eV or less and an electron density of 1×10 11 cm −3 or more; forming a first conductive layer over the first insulating layer; etching the first conductive layer by using a first mask pattern which is intentionally formed to have a portion with a nonuniform thickness and a second mask pattern which is formed to have a uniform thickness by using a photomask or a reticle including an auxiliary pattern having a function of reducing the light intensity; forming a second insulating layer over the first conductive layer after etching the first conductive layer; forming a second conductive layer over the second insulating layer; etching the second conductive layer; forming a third insulating layer over the second conductive layer after etching the second conductive layer; and etching the first insulating layer, the second insulating layer and the third insulating layer to form a contact hole reaching the semiconductor layer.