Halftone phase shift mask blank and halftone phase shift mask
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsYukio INAZUKI, Takuro KOSAKA, Kouhei SASAMOTO, Hideo KANEKO
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Abstract
A halftone phase shift mask blank comprising a transparent substrate and a halftone phase shift film thereon is provided. The halftone phase shift film includes at least one layer composed of a silicon base material having a transition metal content ≤3 at %, a Si+N+O content ≥90 at %, a Si content of 30-70 at %, a N+O content of 30-60 at %, and an O content ≤30 at %, and having a sheet resistance ≤1013/Ω/□. The halftone phase shift film undergoes minimal pattern size variation degradation upon exposure to sub-200 nm radiation, and has chemical resistance and improved processability.
Claims18
A halftone phase shift mask blank comprising a transparent substrate and a halftone phase shift film thereon having a phase shift of 150° to 200° and a transmittance of 3% to 30% with respect to light of wavelength up to 200 nm, wherein
- said halftone phase shift film is a single layer or a multilayer film, and is composed of a silicon base material comprising essentially a transition metal, silicon and nitrogen and optionally oxygen,
- said halftone phase shift film includes at least one layer (A) composed of a silicon base material having a transition metal content of up to 3 at %, a total content of silicon, nitrogen and oxygen of at least 90 at %, a silicon content of 30 to 70 at %, a total content of nitrogen and oxygen of 30 to 60 at %, and an oxygen content of up to 30 at %, and having a sheet resistance of up to 1013Ω/□, wherein the layer (A) is compositionally graded such that the concentration of some or all constituent elements continuously varies in thickness direction.
Dependencies are inferred from the claim text.