Shadow trim line edge roughness reduction

Patent metadata

Field	Value
Publication number	US-9711359-B2
Application number	US-201514826088-A
Country	US
Kind code	B2
Filing date	Aug 13, 2015
Priority date	Aug 13, 2015
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A method for etching an etch layer in a stack over a substrate wherein the etch layer is under a mask layer which is under a patterned organic mask is provided. The stack and substrate is placed on a support in the plasma chamber. A silicon based layer is deposited in situ over the stack. The silicon based layer is etched to form silicon based sidewalls or spacers on sides of the patterned organic mask. The mask layer is selectively etched with respect to the silicon based sidewalls or spacers, wherein the selectively etching the mask layer undercuts the silicon based sidewalls or spacers. The etch layer is selectively etched with respect to the mask layer. The stack and substrate are removed from the support and the plasma chamber.

First claim

What is claimed is:

1. A method for etching a silicon or metal based etch layer in a stack over a substrate wherein the etch layer is under a carbon based mask layer which is under a patterned organic mask, comprising:
placing the stack and substrate on a support in the plasma chamber;
in situ depositing a silicon based layer over the stack, wherein the silicon based layer is a silicon oxide or silicon nitride based layer;
etching the silicon based layer to form silicon based sidewalls or spacers on sides of the patterned organic mask;
selectively etching the carbon based mask layer with respect to the silicon based sidewalls or spacers and the silicon or metal based etch layer, wherein the selectively etching the carbon based mask layer undercuts the silicon based sidewalls or spacers, comprising;
flowing an oxygen based etch gas into the plasma chamber;
forming a plasma from the oxygen based etch gas; and
stopping the flow of the oxygen based etch gas

selectively etching the silicon or metal based etch layer with respect to the carbon based mask layer and simultaneously removing the silicon based sidewalls; and
removing the stack and substrate from the support and the plasma chamber.

2. The method, as recited in claim 1 , wherein the selectively etching the carbon based mask layer selectively etches the carbon based mask layer with respect to the silicon or metal based etch layer.

3. The method, as recited in claim 2 , wherein the carbon based mask layer is a BARC layer.

4. The method, as recited in claim 3 , wherein the silicon or metal based etch layer is over a sublayer, further comprising etching the sublayer after etching the silicon or metal based etch layer.

5. The method, as recited in claim 4 , wherein the silicon or metal based etch layer is a DARC layer.

6. The method, as recited in claim 5 , wherein the silicon based layer is a silicon oxide or silicon nitride based layer.

7. The method, as recited in claim 6 , wherein organic mask is a photoresist mask.

8. The method, as recited in claim 7 , wherein the plasma chamber is an inductively coupled plasma chamber.

Assignees

• Lam Res Corp

Inventors

• Kamp Tom A
• Belen Jr Rodolfo P

Classifications

• H10P76/4085

  characterised by the processes involved to create the masks · CPC title

• H10P76/4083 Primary

  characterised by their behaviours during the lithography processes, e.g. soluble masks or redeposited masks · CPC title

• H10P76/2043

  using an anti-reflective coating · CPC title

• H10P76/405

  characterised by their composition, e.g. multilayer masks · CPC title

• H10P50/692

  characterised by their composition, e.g. multilayer masks or materials · CPC title