Patent ID: 7097946

Claim:
A photomask comprising: a substrate; a translucent film selectively formed on the substrate; and a shading film selectively formed on the translucent film, wherein when the substrate, the translucent film and the shading film have Young's moduli (MPa) E 0 E 1 and E 2 , and film thickness (m) d 0 , d 1 and d 2 respectively, internal stresses (MPa) of the translucent film and the shading film at room temperature are s 1 and s 2 respectively, a covering rate by the translucent film defined by an area in which the shading film is not formed is expressed as h, and coefficients are expressed as k 1 =1.3×10 −8 , k 2 =−9.5×10 −2 , k 3 =6.0×10 −7 , and k 4 =−5.2×10 −2 respectively, the substrate, the translucent film and the shading film satisfy a condition given by the following expression:  1 E 0 · d 0 · { h · ( k 1 · S 1 E 1 · d 1 + k 2 ) + ( k 3 · S 2 E 2 · d 2 + k 4 ) }  ≦ 1.4 × 10 - 4 ⁢ ( m - 1 ) .