Photomask and manufacturing method of semiconductor device
View Patent ↗A photomask according to the embodiment includes a glass substrate which has a first face and a second face located on a side opposite from the first face. The second face includes a transmission area and a light shielding area corresponding to an exposure pattern of a resist film exposed via the glass substrate. The transmission area is oblique to the first face.
1. A photomask comprising:
a glass substrate including a first face and a second face located on a side opposite from the first face, wherein
the second face includes a transmission area and a light shielding area corresponding to an exposure pattern of a resist film exposed via the glass substrate,
the transmission area is oblique to the first face,
the transmission area is formed as a slope shape where a distance to the first face continuously decreases or a stair shape where a distance to the first face decreases step-by-step, and
the transmission area is rectangular in a planar view.
2. The photomask according to claim 1 , wherein
the resist film is located on a stairs area formed on a processed substrate,
the exposure pattern is reduced with a projection lens located between the glass substrate and the processed substrate, and
a height of the transmission area is defined by multiplying a level difference between a top step and a bottom step in the stairs area by a squared of a reduction rate of the projection lens.
3. The photomask according to claim 1 , wherein
the resist film is located on a stairs area formed on a processed substrate, the number of steps of the transmission area is equal to that of the stairs area.