Method for manufacturing reflective mask and apparatus for manufacturing reflective mask
According to one embodiment, a method is disclosed for manufacturing a reflective mask. The method can include forming a reflection layer on a major surface of a substrate. The method can include forming an absorption layer on the reflection layer. The method can include forming a pattern region in the absorption layer. In addition, the method can include forming a light blocking region surrounding the pattern region in the absorption layer and the reflection layer. The forming the light blocking region includes etching-processing the reflection layer using a gas containing chlorine and oxygen.
1. A method for manufacturing a reflective mask comprising a substrate, a reflection layer formed on a major surface of the substrate, the reflection layer including a first layer and a second layer, the first layer including molybdenum, the second layer including silicon, the first layer and the second layer being alternately stacked, an absorption layer formed on the reflection layer, a pattern region formed in the absorption layer, the method comprising:
forming a light blocking region surrounding the pattern region in the absorption layer and the reflection layer; and
the forming the light blocking region including etch-processing both the first layer and the second layer using a gas containing chlorine atom, oxygen atom, and fluorine atom, and
an additive amount of a gas including the oxygen atom being set not less than 5 vol % and not more than 30 vol %, and an additive amount of the gas containing fluorine atom to a gas containing chlorine atom being set not less than 5 vol % and not more than 40 vol % in the forming the light blocking region.
2. The method according to claim 1 , wherein
the absorption layer includes an absorber layer including a nitride of tantalum and an anti-reflection layer including an oxide of tantalum and
the absorber layer and the anti-reflection layer are etch-processed in environments separated from each other, respectively, in the forming the pattern region.
3. The method according to claim 1 , wherein the absorber layer, the anti-reflection layer, and the reflection layer are etch-processed in environments separated from each other, respectively, in the forming the light blocking region.
4. The method according to claim 3 , wherein an environment for etch-processing the absorber layer in the forming the light blocking region is the same environment as an environment for etch-processing the absorber layer in the forming the pattern region.
5. The method according to claim 3 , wherein an environment for etch-processing the anti-reflection layer in the forming the light blocking region is the same environment as an environment for etch-processing the anti-reflection layer in the forming the pattern region.
6. The method according to claim 2 , wherein an oxygen concentration in an environment between an environment for etch-processing the absorber layer and an environment for etch-processing the anti-reflection layer is lower than an oxygen concentration of atmosphere.
7. The method according to claim 1 , wherein a capping layer is further provided between the reflection layer and the absorption layer, and
the forming the light blocking region includes etch-processing an oxide film formed at the capping layer using a chlorine-containing gas or a fluorine-containing gas.
8. The method according to claim 7 , wherein
the capping layer includes silicon and
an environment for etch-processing the capping layer is the same environment as an environment for etch-processing the reflection layer in the forming the light blocking region.
9. The method according to claim 2 , wherein the environments are separated from each other so as to prevent a by-product generated in one etch-processing from entering an environment for performing another etch-processing.
10. The method according to claim 2 , wherein
plasma etch-processing using a fluorine atom-containing gas is performed in etching the anti-reflection layer in the forming the pattern region and the forming the light blocking region and
plasma etch-processing using a chlorine atom-containing gas is performed in etching the absorber layer in the forming the pattern region and the forming the light blocking region.