Patent ID: 7914971

Claim:
A method for manufacturing a semiconductor device, comprising the steps of: forming a first insulating film over a semiconductor layer; forming a conductive film over the first insulating film; forming a first resist pattern over the conductive film, the first resist pattern having a first region and a second region thinner than the first region on a side of the first region by using a light exposure mask including a semi-transmissive portion; forming a gate electrode having a third region and a fourth region thinner than the third region on a side of the third region by etching the conductive film with the use of the first resist pattern; injecting an impurity element into the semiconductor layer with the use of the gate electrode as a mask to form a source region and a drain region outside the gate electrode, and injecting the impurity element into the semiconductor layer through the second region of the gate electrode to form a first impurity region and a second impurity region in a region overlapped with the second region of the gate electrode; forming a second insulating film over the gate electrode; forming a second resist pattern over the second insulating film, the second resist pattern having a first opening and a second opening shallower than the first opening, by using the light exposure mask including the semi-transmissive portion; and forming a third opening and a fourth opening in the second insulating film by etching the second insulating film with the use of the second resist pattern, the first opening being overlapped with the third opening, the second opening being overlapped with the fourth opening, and a depth of the third opening being different from a depth of the fourth opening, wherein the first resist pattern and the second resist pattern are formed by using the light exposure mask in which a sum of a line width L of a light shielding material and a space width S between light shielding materials in the semi-transmissive portion satisfies a conditional expression (n/3)×m≦L+S≦(3n/2)×m when a resolution of a light exposure apparatus is represented by n and a projection magnification is represented by 1/m (m≧1).