Lithography film stack and lithography method
AssigneeUnited Semiconductor (Xiamen) Co., Ltd.
InventorsChing-Shu Lo, Yuan-Chi Pai, MAOHUA REN, WEN YI TAN
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Abstract
A lithography film stack applied to an immersion lithography process includes a photoresist, a wavelength adjusting layer and a top coating layer. The photoresist is disposed on a substrate. The wavelength adjusting layer is disposed on the photoresist. The top coating layer is disposed on the wavelength adjusting layer. A refractive index of the wavelength adjusting layer is greater than a refractive index of the top coating layer and a refractive index of an immersion fluid of the immersion lithography process.
Claims20
A lithography film stack, applied to an immersion lithography process, the lithography film stack comprising:
- a photoresist disposed on a substrate;
- a wavelength adjusting layer disposed on the photoresist;
- and
- a top coating layer disposed on the wavelength adjusting layer, wherein a refractive index of the wavelength adjusting layer is greater than a refractive index of the top coating layer and a refractive index of an immersion fluid of the immersion lithography process.
A lithography method, comprising:
- forming a photoresist on a substrate;
- forming a wavelength adjustment layer on the photoresist;
- forming a top coating layer on the wavelength adjustment layer;
- providing an immersion fluid between the top coating layer and a lens of an exposure device, wherein a refractive index of the wavelength adjusting layer is greater than a refractive index of the top coating layer and a refractive index of the immersion fluid;
- and
- performing an exposure and development step to transfer a pattern of a photomask to the photoresist.
Dependencies are inferred from the claim text.