US 12,463,045 B2
Selective trench modification using directional etch
Tassie Andersen, Salem, MA (US); and Shurong Liang, Lynnfield, MA (US)
Assigned to Applied Materials, Inc.
Filed by Applied Materials, Inc., Santa Clara, CA (US)
Filed on Oct. 19, 2022, as Appl. No. 17/969,333.
Prior Publication US 2024/0136194 A1, Apr. 25, 2024
Prior Publication US 2024/0234156 A9, Jul. 11, 2024
Int. Cl. H01L 21/3065 (2006.01)
CPC H01L 21/3065 (2013.01) 19 Claims
OG exemplary drawing
 
1. A method, comprising:
providing a substrate including a plurality of trenches, wherein a first trench of the plurality of trenches has a first trench length extending in a first direction, wherein a second trench of the plurality of trenches has a second trench length extending in a second direction, wherein the first direction and the second direction are non-parallel, and wherein the first and second trenches are connected; and
delivering ions into the substrate in a reactive ion etching process, wherein the ions are delivered at a non-zero angle relative to a perpendicular extending from the substrate, and wherein the reactive ion etching process increases the first trench length of the first trench without increasing the second trench length of the second trench.