Method of forming a trench isolation structure comprising annealing the oxidation barrier layer thereof in a furnace
AssigneeSamsung Electronics Co., Ltd.
InventorSoo-Jin Hong
Life of this patent
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Abstract
A method of forming a trench isolation structure prevents a nitride liner from being over-etched, i.e., prevents the so-called dent phenomenon from occurring. An etching mask pattern is formed on a semiconductor substrate. A trench is formed in the substrate by using the etching mask pattern as an etching mask. A nitride liner, serving as an oxidation barrier layer, is formed at the sides and bottom of the trench, and is then annealed in a furnace to density the same. In a subsequent etching process, such as that used to remove the etching mask pattern, the densified nitride liner resists being etched. Accordingly, a trench isolation structure having a good profile is produced.
Claims19
A trench isolation method comprising the steps of:
- forming a trench in a semiconductor substrate;
- forming an oxidation barrier layer on an inner wall of the substrate that defines the trench;
- once the oxidation barrier layer has been formed, annealing the structure in a furnace until the oxidation barrier layer is densified throughout substantially its entire thickness;
- and
- subsequently forming an insulating layer in the trench on the annealed oxidation barrier layer.
A trench isolation method comprising the steps of:
- forming an etching mask pattern on a substrate, the etching mask pattern exposing a predetermined area of the substrate;
- etching the exposed area of the substrate using the etching mask pattern as an etching mask to form a trench in the substrate;
- forming an oxidation barrier layer on an inner wall of the substrate that defines the trench;
- once the oxidation barrier layer has been formed, annealing the structure in a furnace until the oxidation barrier layer is densified throughout substantially its entire thickness;
- subsequently forming an insulating layer in the trench on the annealed oxidation barrier layer;
- and
- after the oxidation barrier layer has been annealed, etching away the etching mask pattern.
Dependencies are inferred from the claim text.