Methods of forming patterns for semiconductor device structures

Patent metadata

Field	Value
Publication number	US-9465287-B2
Application number	US-201514928159-A
Country	US
Kind code	B2
Filing date	Oct 30, 2015
Priority date	Jan 22, 2013
Publication date	Oct 11, 2016
Grant date	Oct 11, 2016

Abstract

Methods of forming a pattern in a semiconductor device structure include deprotecting an outer portion of a first photosensitive resist material, forming a second photosensitive resist material, exposing portions of the first and second photosensitive resist materials to radiation, and removing the deprotected outer portion of the first photosensitive resist material and the exposed portions of the first and second photosensitive resist materials. Additional methods include forming a first resist material over a substrate to include a first portion and a relatively thicker second portion, deprotecting substantially the entire first portion and an outer portion of the second portion while leaving an inner portion of the second portion protected, and forming a second resist material over the substrate. A portion of the second resist material is exposed to radiation, and deprotected and exposed portions of the first and second resist materials are removed.

First claim

What is claimed is:

1. A method of forming a pattern in a semiconductor device structure, the method comprising:
forming a patterned first photosensitive resist material over a substrate;
forming a second photosensitive resist material over the substrate and over the patterned first photosensitive resist material;
selectively exposing at least some of the patterned first photosensitive resist material through the second photosensitive resist material and at least some of the second photosensitive resist material to radiation; and
selectively removing the at least some of the patterned first photosensitive resist material and the at least some of the second photosensitive resist material exposed to the radiation with a developer solution.

2. The method of claim 1 , further comprising selecting the first photosensitive resist material to comprise one or more of a tert-butoxycarbonyl group or a polyether material based on alkoxypyrimidine units.

3. The method of claim 1 , wherein forming the patterned first photosensitive resist material over the substrate comprises exposing at least some of the first photosensitive resist material to another radiation through a mask.

4. The method of claim 3 , further comprising contacting the at least some of the first photosensitive resist material exposed to the another radiation through the mask with a developer solution to form trenches in the first photosensitive resist material.

5. The method of claim 1 , wherein forming the patterned first photosensitive resist material over the substrate comprises forming a pattern in the first photosensitive resist material by photolithography.

6. The method of claim 1 , further comprising contacting the patterned first photosensitive resist material with an acid to form chemically modified outer portions of the first photosensitive resist material that are more soluble in a developer solution than inner portions of the first photosensitive resist material that are unexposed to the acid.

7. The method of claim 6 , wherein contacting the patterned first photosensitive resist material with the acid comprises diffusing one or more of triflic acid perfluorobutanesulfonic acid into the patterned first photosensitive resist material.

8. The method of claim 6 , wherein contacting the patterned first photosensitive resist material with the acid to form the chemically modified outer portions of the first photosensitive resist material comprises exposing the acid and the semiconductor device structure to a temperature between about 80° C. and about 130° C. to diffuse the acid into the patterned first photosensitive resist material.

9. The method of claim 1 , wherein forming the second photosensitive resist material over the substrate and over the patterned first photosensitive resist material comprises forming the second photosensitive resist material between trenches of the first photosensitive resist material and over the patterned first photosensitive resist material.

10. The method of claim 1 , further comprising selecting the second photosensitive resist material to comprise one or more of a methacrylate material, a polyhydroxystyrene material, a poly(butane-1-sulfone) material, an acrylate material, and a copolymer of chloromethacrylate and methylstyrene.

11. The method of claim 1 , wherein selectively exposing the at least some of the patterned first photosensitive resist material through the second photosensitive resist material and the at least some of the second photosensitive resist material to the radiation comprises simultaneously exposing the at least some of the patterned first photosensitive resist material and the at least some of the second photosensitive resist material to the radiation through a mask.

12. A method of forming a semiconductor device, the method comprising:
forming a patterned first resist material on a substrate;
exposing outer portions of the patterned first resist material to an acid to form chemically modified outer portions of the patterned first resist material;
forming a second resist material over the patterned first resist material;
selectively exposing at least some of the patterned first resist material and at least some of the second resist material to radiation; and
removing, with a developer solution, the chemically modified outer portions of the patterned first resist material, the at least some of the patterned first resist material exposed to the radiation, and the at least some of the second resist material exposed to the radiation.

13. The method of claim 12 , wherein selectively exposing the at least some of the patterned first resist material to the radiation comprises exposing the at least some of the patterned first resist material to the radiation through at least some of the chemically modified outer portions of the patterned first resist material.

14. The method of claim 12 , further comprising forming transferring a pattern to the substrate after the removing, with the developer solution, the chemically modified outer portions of the patterned first resist material, the at least some of the patterned first resist material exposed to the radiation, and the at least some of the second resist material exposed to the radiation.

15. A method of forming a semiconductor device, the method comprising:
forming a patterned first resist material comprising a first portion having a smaller lateral width than a second portion of the patterned first resist material on a substrate;
diffusing an acid through substantially all of the first portion of the patterned first resist material and through an outer portion of the second portion of the patterned first resist material;
forming a second resist material adjacent the first portion of the patterned first resist material and the second portion of the patterned first resist material; and
selectively removing the first portion of the patterned first resist material, the outer portion of the second portion of the patterned first resist material, and at least a portion of the second resist material.

16. The method of claim 15 , wherein selectively removing the first portion of the patterned first resist material, the outer portion of the second portion of the patterned first resist material, and at least a portion of the second resist material comprises exposing the first portion of the patterned first resist material, the outer portion of the second portion of the patterned first resist material, and the at least a portion of the second resist material to radiation through a mask.

17. The method of claim 15 , further comprising transferring a pattern of the patterned first resist material and the second resist material to the substrate after selectively removing the first portion of the patterned first resist material, the outer portion of the second portion of the patterned first resist material, and the at least the portion of the second resist material.

Assignees

• Micron Technology Inc

Inventors

• Light Scott L
• He Yuan
• Many Michael A
• Hyatt Michael

Classifications

• H10P76/204

  of organic photoresist masks · CPC title

• H10P50/71

  using masks for conductive or resistive materials · CPC title

• G03F7/2022

  Multi-step exposure, e.g. hybrid; backside exposure; blanket exposure, e.g. for image reversal; edge exposure, e.g. for edge bead removal; corrective exposure · CPC title

• G03F7/095

  having more than one photosensitive layer (G03F7/075 takes precedence) · CPC title

• G03F7/0035 Primary

  Multiple processes, e.g. applying a further resist layer on an already in a previously step, processed pattern or textured surface · CPC title