Mask for light exposure and process for production of the same
AssigneeKabushiki Kaisha Toshiba
InventorsShin-ichi Ito, Takayuki Iwamatsu
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Abstract
There is disclosed a mask for light exposure which comprises being provided with a light transparent substrate and a mask pattern formed on the light transparent substrate, the mask pattern comprising a light screening pattern composed of a material which screens the exposure light and transmits the light having the longer wavelength than that of the exposure light and a phase shift pattern formed by engraving a part of the light transparent substrate.
Claims25
A mask for light exposure which is provided with a light transparent substrate and a mask pattern formed on said light transparent substrate, said mask pattern comprising a light screening pattern composed of material which screens the exposure light and transmits a phase measuring light having a wavelength longer than that of the exposure light and a phase shift pattern formed by engraving a part of the light transparent substrate.
In a method for production of a mask for light exposure provided with a light transparent substrate and a mask pattern formed on the light transparent substrate, said mask pattern comprising a light screening pattern composed of a material which screens the exposure light and transmits the light having the longer wavelength than that of the exposure light and a phase shift pattern formed by engraving a part of the light transparent substrate, said process comprising calculating an etched depth of the light transparent substrate by determining the optical image of the light passing through the light screening pattern and the light passing through an opening of the light screening pattern or determining the phase difference between said two kinds of lights using the phase measuring light having the longer wavelength than that of the exposure light.
In a method for production of a mask for light exposure provided with a light transparent substrate and a mask pattern, formed on said light transparent substrate, comprising a light screening pattern and a phase shift pattern formed by engraving a part of the light transparent substrate, said process comprising the following steps:
- a step of forming the light screening pattern composed of a material which screens the exposure light and transmits a phase measuring light having a longer wavelength than that of the exposure light, on the light transparent substrate,
- a step of etching the substrate using the light screening pattern and a resist as a mask while selectively masking an opening of the light screening pattern and determining the phase difference between the light passing through the light screening pattern and the light passing through the opening of the light screening pattern using the phase measuring light having the longer wavelength than that of the exposure light, then stopping etching at a time when the desired phase difference is obtained, and
- a step of removing the resist.
In a method for production of a mask for light exposure provided with a light transparent substrate and a mask pattern, formed on the light transparent substrate, comprising a light screening pattern and a phase shift pattern formed by engraving a part of the light transparent substrate, said process comprising the following steps:
- a step of forming the light screening pattern composed of a material which screens the exposure light and transmits a phase measuring light having the longer wavelength than that of the exposure light, on the light transparent substrate,
- a step of etching the substrate using the light screening pattern and a resist as a mask while selectively masking an opening of the light screening pattern with the resist and determining the phase difference between the light passing through the light screening pattern and the light passing through the opening of the light screening pattern using the phase measuring light having a wavelength such that the light screening material transmits, then stopping etching at a time when the desired phase difference is obtained,
- a step of, after removal of the resist, etching the substrate using the light screening pattern as a mask while determining the phase difference between the light passing through the light screening pattern and the light passing through the opening of the light screening pattern using the phase measuring light having the longer wavelength than that of the exposure light, then stopping etching at a time when the desired phase difference is obtained.
Dependencies are inferred from the claim text.