Synthetic quartz glass member for excimer laser and method of making
AssigneesShin-Etsu Chemical Co., Ltd., Shin-Etsu Quartz Products Co., Ltd.
InventorsHisatoshi Otsuka, Kazuo Shirota, Akira Fujinoki
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Abstract
A synthetic quartz glass member having (i) a change of transmittance at 193 nm of up to 0.002 cm−1 as expressed in extinction coefficient when 4×104 shots of ArF excimer laser light are irradiated at 2 mJ/cm2/pulse, (ii) an initial transmittance of at least 99.6% at 193 nm, (iii) a hydrogen molecule content of at least 5×1017 molecules/cm3, (iv) a refractive index amplitude of up to 1×10−6, and (v) a birefringence of up to 1 nm/cm finds use in an excimer laser because it experiences a minimized change of light transmittance.
Claims20
A synthetic quartz glass member for an excimer laser, having
- (i) a change of transmittance at wavelength 193 nm of up to 0.002 cm−1 as expressed in extinction coefficient when 4×104 shots of ArF excimer laser light are irradiated at 2 mJ/cm2/pulse,
- (ii) an initial transmittance of at least 99.6% at 193 nm,
- (iii) a hydrogen molecule content of at least 5×1017 molecules/cm3,
- (iv) a refractive index amplitude of up to 1×10−6, and
- (v) a birefringence of up to 1 nm/cm.
A synthetic quartz glass member, having
- (i) a change of transmittance at wavelength 193 nm of up to 0.002 cm−1 as expressed in extinction coefficient when 4×104 shots of ArF excimer laser light are irradiated at 2 mJ/cm2/pulse,
- (ii) an initial transmittance of at least 99.6% at 193 nm,
- (iii) a hydrogen molecule content of at least 5×1017 molecules/cm3,
- (iv) a refractive index amplitude of up to 1×10−6, and
- (v) a birefringence of up to 1 nm/cm.
Dependencies are inferred from the claim text.