Diamond-like carbon as mandrel

Patent metadata

Field	Value
Publication number	US-10954129-B2
Application number	US-201816002218-A
Country	US
Kind code	B2
Filing date	Jun 7, 2018
Priority date	Jun 8, 2017
Publication date	Mar 23, 2021
Grant date	Mar 23, 2021

Abstract

A method of fabricating a semiconductor structure is described. The method comprises forming at least one mandrel on a substrate, the at least one mandrel comprising a diamond-like carbon and having a top and two opposing sidewalls, the diamond-like carbon comprising at least 40% sp3 hybridized carbon atoms. The mandrel may be used in Self-Aligned Multiple Patterning (SAMP) processes.

First claim

What is claimed is:

1. A method of fabricating a semiconductor structure, the method comprising:
forming a film stack on a substrate by plasma enhanced chemical vapor deposition (PECYD) at a temperature ranging from −50° C. to 600° C. and a pressure ranging from 0.1 mTorr to 10 Torr, the film stack comprising a pre-mandrel material;
forming a barrier layer on a top surface of the pre-mandrel material, the bather layer comprising spin-on-carbon;
forming a mask layer on a portion of a top surface of the barrier layer;
removing the barrier layer and pre-mandrel material that is not covered by the mask layer;
removing the mask layer and the barrier layer that is covered by the mask layer to form at least one mandrel on a silicon-containing layer formed on a titanium nitride layer on the substrate, the at least one mandrel comprising a diamond-like carbon and having a top surface and two opposing sidewalls, the diamond-like carbon comprising at least 40% spa hybridized carbon atoms;
depositing at least one layer of a spacer film on the at least one mandrel;
etching the spacer film from the top surface of the at least one mandrel leaving the spacer film on the two opposing sidewalls of the at least one mandrel;
removing the at least one mandrel to leave the spacer film from the two opposing sidewalls of the at least one mandrel and expose portions of the silicon-containing layer; and
etching the exposed portions of the silicon-containing layer to form adjacent pairs of substrate features.

2. The method of claim 1 , wherein the diamond-like carbon is etch selective and strip selective over spin-on-carbon (SOC).

3. The method of claim 1 , wherein the diamond-like carbon has a stress less than −500 MPa.

4. The method of claim 1 , wherein the diamond-like carbon has a density greater than 1.8 g/cc.

5. The method of claim 1 , wherein the diamond-like carbon comprises from about 50% to about 90% sp 3 hybridized carbon atoms.

6. The method of claim 1 , wherein the diamond-like carbon comprises about 60% sp 3 hybridized carbon atoms.

7. The method of claim 1 , wherein the diamond-like carbon has a Young's modulus greater than 150 GPa, measured at room temperature.

8. The method of claim 1 , wherein the at least one mandrel is formed by pulsed plasma enhanced chemical vapor deposition (PECVD).

9. The method of claim 1 , wherein the spacer film comprises silicon oxide.

10. The method of claim 1 , wherein the spacer film is a bather layer comprising spin-on-carbon (SOC).

Assignees

• Applied Materials Inc

Inventors

• Koshizawa Takehito
• Venkatasubramanian Eswaranand
• Manna Pramit
• Lu Chi
• Lang Chi-I
• Fung Nancy
• Mallick Abhijit Basu

Classifications

• H10P76/405

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

• H10P50/695

  characterised by the process involved to create the mask, e.g. lift-off masks or sidewalls or to modify the mask · CPC title

• H10P50/692

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

• H10P50/283

  by chemical means · CPC title

• H10P50/73

  using masks for insulating materials · CPC title