Reflective mask blank and reflective mask, and methods for manufacturing reflective mask blank and reflective mask
AssigneeToppan Printing Co., Ltd.
InventorsMasahito TANABE, Norihito Fukugami, Yo Sakata, Tooru Komizo, Takashi Haraguchi
Life of this patent
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Abstract
A reflective mask blank, a reflective mask, and methods for manufacturing those, which suppress reflectance at a light-shielding frame. The reflective mask includes a substrate, a multilayered reflective layer formed on the substrate, an absorption layer formed on the multilayered reflective layer, and a frame-shaped light-shielding frame area at which the absorption layer has a film thickness larger than a film thickness at other areas. The multilayered reflective layer is diffused and mixed at the light-shielding frame area through melting.
Claims9
A reflective mask blank comprising:
- a substrate;
- a multilayered reflective layer formed on the substrate;
- an absorption layer formed on the multilayered reflective layer;
- and
- a frame-shaped light-shielding frame area at which the absorption layer has a film thickness larger than a film thickness at other areas.
A method for manufacturing a reflective mask blank, the method comprising at least:
- preparing a low thermal-expansion substrate and forming a resist film on a surface of the low thermal-expansion substrate;
- forming a reverse pattern of a frame-shaped light-shielding frame pattern on the resist film;
- forming a light-shielding frame area on a surface of the low thermal-expansion substrate by etching the low thermal-expansion substrate using, as a mask, the reverse pattern formed on the resist film;
- stripping the resist film, and then laminating a multilayered reflective layer, a protective layer, and an absorption layer in this order on the surface of the low thermal-expansion substrate on which the light-shielding frame area is formed;
- and
- planarizing a surface of the deposited absorption layer with Chemical Mechanical Polishing method.
Dependencies are inferred from the claim text.