Patent ID: 8461056

Claim:
A self-aligned wet etching process, comprising the steps of: Step S 1 : etching a substrate including an etch protection layer on a surface thereof to form a plurality of trenches spaced from each other; Step S 2 : sequentially forming an insulating layer and an etch stop layer on a surface of each of the plurality of trenches to form an accommodation space inside the etch stop layer; Step S 3 : filling a primary insulator inside the accommodation space, wherein the primary insulator integrates with the etch stop layer and the insulating layer to form a multi-layer isolator; Step S 4 : removing the etch protection layer to expose a portion of the isolator outside the substrate; Step S 5 : removing the insulating layer exposing outside the substrate through a wet etching solution, wherein the primary insulator is protected by the etch stop layer and exempted from being etched by the wet etching solution; Step S 6 : removing the etch stop layer exposing outside the substrate to expose a portion of the primary insulator outside the substrate; and Step S 7 : forming a plurality of electric contactors on the substrate that are separated by the primary insulator, wherein in the Step S 1 , the substrate is etched in a first direction and a second direction vertical to the first direction to respectively form a plurality of first trenches spaced from each other and a plurality of second trenches spaced from each other with a plurality of pillars formed between the plurality of first trenches and the plurality of second trenches.