US 11,810,787 B2
Semiconductor structure formation method and mask
Jisong Jin, Shanghai (CN)
Assigned to Semiconductor Manufacturing International (Shanghai) Corporation, Shanghai (CN); and Semiconductor Manufacturing International (Beijing) Corporation, Beijing (CN)
Filed by Semiconductor Manufacturing International (Shanghai) Corporation, Shanghai (CN); and Semiconductor Manufacturing International (Beijing) Corporation, Beijing (CN)
Filed on Mar. 31, 2021, as Appl. No. 17/218,809.
Claims priority of application No. 202011137109.1 (CN), filed on Oct. 22, 2020.
Prior Publication US 2022/0130672 A1, Apr. 28, 2022
Int. Cl. H01L 21/033 (2006.01); H01L 21/311 (2006.01); H01L 21/768 (2006.01); H01L 21/3215 (2006.01); H01L 21/3115 (2006.01)
CPC H01L 21/0337 (2013.01) [H01L 21/31144 (2013.01); H01L 21/76816 (2013.01); H01L 21/0332 (2013.01); H01L 21/31155 (2013.01); H01L 21/3215 (2013.01); H01L 21/32155 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A semiconductor structure formation method, comprising:
providing a base that comprises a target layer used for forming a target pattern;
forming a mandrel material layer on the base, wherein the mandrel material layer comprises a first region used for forming a mandrel layer, and a second region encircling the first region and used for forming an anti-etching layer;
performing ion doping on the mandrel material layer in the second region, the ion doping being suitable for increasing an etching resistance of the mandrel material layer, wherein the mandrel material layer doped with ions that is located in the second region serves as the anti-etching layer, and the mandrel material layer not doped with ions that is located in the first region serves as the mandrel layer;
forming a first trench that runs through, along a first direction, at least part of the mandrel material layer in the first region, wherein a direction perpendicular to the first direction is a second direction, and part of the mandrel material layer in the first region remains at two sides of the first trench along the second direction, the first trench comprises a first side wall along the second direction, and a second side wall opposite to the first side wall and parallel to the first side wall, the second side wall of the first trench is flush with a boundary of the first region at the same side, or the second side wall of the first trench is located in the neighboring second region;
forming spacers on side walls of the first trench, so that the spacers form a first groove by encircling the first groove;
removing the mandrel layer after the ion doping is performed and the spacers are formed, and forming second grooves in the anti-etching layer that are located at two sides of the first groove; and
etching, using the anti-etching layer and the spacers as masks, the target layer below the first groove and the second grooves, to form the target pattern.