Method for forming fine structure
AssigneeCanon Kabushiki Kaisha
InventorsYuichi Iwasaki, Ichiro Tanaka
Life of this patent
Estimating the term…
Abstract
In order to form three or more steps on a substrate with high precision, a first mask is formed to an area on the substrate corresponding with every other step, and also etching is performed on the area of the substrate to which the first mask is not formed, a second mask is formed to an area on the substrate to which the first mask has not been formed, and also etching is performed on the area on the substrate to which the first and the second masks are not formed.
Claims36
A lithographic method for manufacturing a diffraction optical device having multi-stepped, stair-like structures formed on a substrate, wherein each structure has at least three stair-like steps, said method comprising the steps of:
- a first step comprising forming a first masking pattern comprising a first masking material in a pattern of lines, spaces and recessed portions on said substrate, wherein the recessed portions are in the spaces of said first masking pattern;
- a second step of forming a second masking pattern comprising a second masking material in a pattern of lines and spaces on said substrate by filling the recessed portions formed on said substrate by said first step with said second masking material, wherein the spaces of said second masking pattern correspond to the lines of the first masking pattern;
- a third step comprising forming a third masking pattern by etching a portion of the lines of said first and second masking materials;
- and
- a fourth step comprising etching said substrate through said third masking pattern, said third masking pattern comprising non-etched portions of said first and second masking patterns.
A method for manufacturing a mold for manufacturing diffraction optical devices, said method comprising the steps of:
- providing a base material that is partially covered with a first mask having diffraction pattern cycle portions;
- etching portions of the base material not covered with said first mask;
- then covering portions of said first mask other than the diffraction pattern cycle portions, with a second mask;
- repeating the above steps at least once;
- then covering the portions of the base material not covered with said first mask with a third mask;
- covering portions of said first mask other than the diffraction pattern cycle portions with said third mask and a fourth mask;
- removing the portions of said first mask that are not masked with said third and fourth masks;
- then etching said base material;
- and
- repeating the above steps at least once.
A method for manufacturing diffraction optical devices, said method comprising the steps of:
- providing a base material that is partially covered with a first mask having diffraction pattern cycle portions;
- etching portions of the base material not covered with said first mask;
- then covering portions of said first mask other than the diffraction pattern cycle portions with a second mask;
- repeating the above steps at least once;
- then covering the portions of the base material not covered with said first mask with a third mask;
- covering portions of said first mask other than the diffraction pattern cycle portions with said third mask and a fourth mask;
- removing the portions of said first mask that are not masked with said third and fourth masks;
- then etching said base material;
- and
- repeating the above steps at least once.
A method for manufacturing diffraction optical devices, said method comprising the steps of:
- providing a base material that is partially covered with a first mask having diffraction pattern cycle portions;
- etching portions of the base material not covered with said first mask;
- then covering portions of said first mask other than the diffraction pattern cycle portions with a second mask;
- etching portions of the base material not covered with a mask;
- repeating the above steps at least once;
- then covering the portions of the base material not covered with said first mask with a third mask;
- covering portions of said first mask other than the diffraction pattern cycle portions with said third mask and a fourth mask;
- removing the portions of said first mask that are not masked;
- then repeating at least once a step of etching said base material;
- removing said third mask and fourth mask;
- covering the portions of the base material not covered with said first mask with a fifth mask;
- then covering every other portion of said first mask with a sixth mask;
- removing the portions of said first mask that are not covered by said fifth and sixth mask;
- then covering every other portion of said fifth mask with a seventh mask;
- removing the portions of said fifth mask that are not covered by said seventh mask;
- etching said base material at the portions not covered by said fifth mask and said first mask;
- and finally removing the remaining said fifth mask and said first mask.
A lithographic method for forming an element having multi-stepped, stair-like structures on a substrate, wherein each structure has three or more stair-like steps, comprising:
- a step comprising alternately forming first and second masks with differing materials;
- a step comprising etching portions of said first and second masks to form a third mask;
- and
- a step comprising etching the substrate through said third mask, said third mask comprising non-etched portions of said first and second masks.
A method for forming three or more steps on a substrate, said method comprising the steps of:
- forming a first mask on an area of said substrate corresponding with every other step, and performing at least one of etching or deposition on an area of said substrate on which said first mask is not formed;
- and
- forming a second mask on an area of said substrate on which said first mask has not been formed, and performing at least one of etching or deposition on the area of said substrate on which neither of said first and said second masks is formed.
A lithographic method of manufacturing an element having multi-stepped, stair-like structures on a substrate, wherein each structure has at least three stair-like steps, comprising:
- (a) defining a position of a first stair-like step in said each stair-like structure by a masking pattern of lines formed on the substrate;
- and
- (b) defining the position of each subsequent stair-like step by a portion of the lines of the masking pattern formed in said step (a) and another masking pattern.
Dependencies are inferred from the claim text.