Self-aligned single dummy fin cut with tight pitch

Patent metadata

Field	Value
Publication number	US-2018082850-A1
Application number	US-201715813518-A
Country	US
Kind code	A1
Filing date	Nov 15, 2017
Priority date	Aug 9, 2016
Publication date	Mar 22, 2018
Grant date	—

Abstract

A method of forming a semiconductor device and resulting structures having a dummy semiconductor fin removed from within an array of tight pitch semiconductor fins by forming a first spacer including a first material on a substrate; forming a second spacer including a second material on the substrate, the second spacer adjacent to the first spacer; and applying an etch process to the first spacer and the second spacer; wherein the etch process removes the first spacer at a first etch rate; wherein the etch process removes the second spacer at a second etch rate; wherein the first etch rate is different than the second etch rate.

First claim

What is claimed is:

1 . An apparatus comprising:
a first spacer comprising a first material formed on a substrate; and a second spacer comprising a second material formed on the substrate, the second spacer adjacent to the first spacer on the substrate; wherein an etch process applied to the first spacer removes the first spacer at a first etch rate; wherein the etch process applied to the second spacer removes the second spacer at a second etch rate; wherein the first etch rate is different than the second etch rate.

2 . The apparatus of claim 1 , further comprising:
a first set of spacers of the first material deposited on the substrate; a second set of spacers of the second material deposited on the substrate; a mask material layer formed on the first set and on the second set; an opening in the mask material layer, the opening having first and second sidewalls; the first sidewall positioned over a first spacer of the second set of spacers, the first spacer of the second set of spacers adjacent to the first spacer of the first set of spacers; and the second sidewall positioned over a second spacer of the second set of spacers, the second spacer of the second set of spacers opposite to the first spacer of the second set of spacers and adjacent to the first spacer of the first set of spacers.

3 . The apparatus of claim 2 , wherein the first spacer of the first set of spacers has been removed by an etch selective to the second material and the mask material layer.

4 . The apparatus of claim 3 , further comprising a plurality of fins, each fin formed in a space between adjacent spacers by removing portions of the substrate.

5 . The apparatus of claim 1 , wherein the spacing between each adjacent spacer is less than about 40 nm.

6 . An apparatus comprising:
a first spacer comprising a first material formed on a substrate, the first material comprising a first etch characteristic; and a second spacer formed on the substrate and adjacent to the first spacer, the second spacer comprising a metal oxide, the metal oxide comprising a second etch characteristic; wherein the first and second etch characteristics are dissimilar.

7 . The apparatus of claim 6 , wherein a distance between the first and second spacers is less than about 40 nm.

8 . The apparatus of claim 6 , wherein the first material comprises an oxide.

9 . The apparatus of claim 8 , wherein the oxide is silicon dioxide.

10 . The apparatus of claim 6 , wherein the metal oxide comprises aluminum oxide.

11 . The apparatus of claim 6 , wherein the first and second etch characteristics are etch rates with respect to a same etchant.

12 . The apparatus of claim 11 , wherein the first etch characteristic is greater than the second etch characteristic and the second etch characteristic is zero or effectively zero.

13 . The apparatus of claim 6 , wherein the metal oxide is formed by sequential infiltration synthesis (SIS) of a polymer.

14 . The apparatus of claim 13 , wherein the polymer is formed by directed self-assembly (DSA) of a block copolymer.

15 . A two color hard mask comprising:
a plurality of first hard masks comprising a first material formed on a substrate, the first material comprising a first etch characteristic; and a plurality of second hard masks comprising a second material formed on the substrate such that the first and second hard masks alternate on the substrate, the second material comprising a polymer infiltrated with a metal by sequential infiltration synthesis (SIS), the second material comprising a second etch characteristic; wherein the first and second etch characteristics are dissimilar.

16 . The apparatus of claim 15 , wherein a distance between each pair of first and second hard masks is less than about 40 nm.

17 . The apparatus of claim 15 , wherein the first material comprises an oxide.

18 . The apparatus of claim 15 , wherein the second material comprises aluminum oxide.

19 . The apparatus of claim 15 , wherein the first and second etch characteristics are etch rates with respect to a same etchant.

20 . The apparatus of claim 19 , wherein the first etch characteristic is greater than the second etch characteristic and the second etch characteristic is zero or effectively zero.

Assignees

• IBM

Inventors

• Cheng Kangguo
• Chi Cheng
• Liu Chi-Chun
• Xu Peng

Classifications

• H10P76/4085

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

• H10P50/283

  by chemical means · CPC title

• H10P50/694 Primary

  characterised by their behaviour during the process, e.g. soluble masks or redeposited masks · CPC title

• H01L21/3085 Primary

  Electricity · mapped topic

• H01L21/31116

  Electricity · mapped topic