Method for creating a pattern in a material and semiconductor structure processed therewith
View Patent ↗A method of manufacturing a semiconductor device with precision patterning is disclosed. A structure of a small dimension is created in a material, such as a semiconductor material, using a first and a second pattern, the patterns being identical but displaced over a distance with respect to each other. Two mask layers are used, wherein the first pattern is etched into the upper mask layer with a selective etch, and the second pattern is created on the upper mask layer or on the lower mask layer at locations where the upper mask layer has been removed. A part of the lower mask layer and/or the upper mask layer is etched according to the second pattern, resulting in a mask formed by remaining parts of the lower and upper mask layers, the mask having a structure with a dimension determined by a displacement of the second pattern with respect to the first pattern.
1. A method of manufacturing a semiconductor device wherein a pattern is created in a material, the method comprising:
covering the material with a lower mask layer;
covering the lower mask layer with an upper mask layer;
creating a first pattern on the upper mask layer via a lithographic mask;
removing a part of the upper mask layer in dependency on the first pattern;
creating, via the lithographic mask, a second pattern on the upper mask layer or on the lower mask layer at locations where the upper mask layer has been removed, the lithographic mask being displaced over a distance such that the second pattern is displaced with respect to the first pattern;
removing a part of at least the lower mask layer in accordance with at least the second pattern; and
removing a part of the material in accordance with remaining parts of the lower and the upper mask layers.
2. The method according to claim 1 , wherein removing a part of at least the lower mask layer in accordance with at least the second pattern comprises:
removing a part of the lower mask layer in accordance with the second pattern overlaid with a pattern formed by a remaining part of the upper mask layer.
3. The method according to claim 1 , wherein removing a part of at least the lower mask layer in accordance with at least the second pattern comprises:
removing a part of the upper mask layer in accordance with the second pattern; and
removing a part of the lower mask layer in accordance with a pattern formed by the upper mask layer.
4. The method according to claim 1 , wherein the removal of a part of the lower mask layer or the upper mask layer in accordance with the first or the second pattern comprises selectively etching the respective layer in accordance with the pattern.
5. The method according to claim 1 , wherein the material comprises at least one of an organic and an inorganic material.
6. The method according to claim 5 , wherein the material comprises a layer of organic material covering a layer of inorganic material.
7. The method according to claim 6 , wherein the removal of a part of the material in accordance with the remaining parts of the lower and the upper mask layers comprises:
removing a part of the organic material in accordance with the mask formed by remaining parts of the lower and the upper mask layers;
removing a part of the inorganic material in accordance with the mask formed by a remaining part of at least the organic material; and
removing the remaining part of the organic material.
8. The method according to claim 1 , further comprising removing the remaining parts of the lower and upper mask layers.