Photomask
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorTadayoshi Imai
Life of this patent
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Abstract
In a photomask according to the present invention, an attenuating film is formed on one major surface of a transparent glass substrate. The attenuating film has an opening, in which a phase-shifting film is formed. A non-transparent film for shutting out incident light is formed a portion of the attenuating film while being contiguous with the phase-shifting film. Thus, the intensity of light through the attenuating film substantially coincides with the intensity of the phase-shifting film. As a result, the peak intensity passing through the photomask becomes constant.
Claims8
A photomask comprising:
- a transparent glass substrate having one major surface;
- an attenuating film formed on the major surface of said transparent glass substrate for decaying incident light, said attenuating film having an opening;
- a phase-shifting film formed on a portion of the major surface, the portion corresponding to said opening of said attenuating film;
- and
- a non-transparent film for shutting out incident light, said non-transparent film being formed on a portion of said attenuating film while being contiguous with said phase-shifting film;
- said attenuating film having an amount of attenuation such that light transmitted through said attenuating film has an intensity corresponding to light passing through said phase-shifting film.
A photomask for transferring a predetermined pattern comprising:
- a transparent glass substrate having one major surface;
- an attenuating film formed on the major surface of said transparent glass substrate for decaying incident light;
- a phase-shifting film formed on the major surface of said transparent glass substrate, said phase-shifting film located on said major surface such that a space is provided between said phase-shifting film and said attenuating film;
- and
- a non-transparent film formed on the major surface of said transparent glass substrate, said non-transparent film provided in said space such that said non-transparent film is between said attenuating film and said phase-shifting film;
- said attenuating film having an amount of attenuation such that light transmitted through said attenuating film has an intensity corresponding to light passing through said phase-shifting film.
Dependencies are inferred from the claim text.