Method of reducing undesired light influence in extreme ultraviolet exposure

Patent metadata

Field	Value
Publication number	US-12517434-B2
Application number	US-202418663843-A
Country	US
Kind code	B2
Filing date	May 14, 2024
Priority date	Oct 31, 2018
Publication date	Jan 6, 2026
Grant date	Jan 6, 2026

Abstract

A method of generating a layout pattern includes disposing a photoresist layer of a resist material on a substrate and disposing a top layer over of the photoresist layer. The top layer is transparent for extreme ultraviolet (EUV) radiation and the top layer is opaque for deep ultraviolet (DUV) radiation. The method further includes irradiating the photoresist layer with radiation generated from an EUV radiation source. The radiation passes through the top layer to expose the photoresist layer.

First claim

What is claimed is:

1 . A method of manufacturing a semiconductor device, comprising:
forming a photoresist layer over a wafer; forming a spectral filter to a thickness over the photoresist layer, wherein the spectral filter is in direct contact with the photoresist layer and comprises a polysilicon; and generating ultraviolet radiation that includes extreme ultraviolet (EUV) radiation and deep ultraviolet (DUV) radiation, wherein the thickness of the spectral filter is sufficient to reflect the DUV radiation, the spectral filter comprises a membrane including the polysilicon deposited over a silicon nitride layer, and wherein the membrane is in direct contact with the photoresist layer, and the EUV radiation passes through the spectral filter and exposes the photoresist layer.

2 . The method according to claim 1 , comprising:
forming the photoresist layer with a uniform thickness on the wafer while the wafer is rotating.

3 . The method according to claim 1 , further comprising:
heating the photoresist layer in a post-application baking operation prior to forming the spectral filter over the photoresist layer.

4 . The method of claim 1 , wherein the EUV radiation has a wavelength between 10 nm and 100 nm and the DUV radiation has a wavelength between 190 nm to 365 nm.

5 . The method of claim 1 , further comprising:
performing a post-exposure bake (PEB) after generating the ultraviolet radiation.

6 . The method of claim 1 , further comprising:
removing the spectral filter.

7 . The method of claim 6 , further comprising:
applying a developer to the photoresist layer to produce a patterned layer over the wafer.

8 . A method of manufacturing a semiconductor device, comprising:
calculating a thickness of a spectral filter by selecting a first wavelength of a deep ultraviolet (DUV) radiation, wherein the thickness of the spectral filter is based on the first wavelength; depositing the spectral filter to the calculated thickness over a photoresist layer, wherein the spectral filter is in direct contact with the photoresist layer and comprises a polysilicon; and generating ultraviolet radiation that includes extreme ultraviolet (EUV) radiation and the DUV radiation, wherein the EUV radiation passes through the spectral filter and exposes the photoresist layer, the spectral filter comprises a membrane including the polysilicon deposited over a silicon nitride layer, wherein the membrane is in direct contact with the photoresist layer, and the spectral filter attenuates the DUV radiation.

9 . The method according to claim 8 , further comprising:
heating the photoresist layer in a post-application baking operation prior to forming the spectral filter over the photoresist layer.

10 . The method of claim 8 , wherein the EUV radiation has a wavelength between 10 nm and 100 nm.

11 . The method of claim 8 , wherein the calculated thickness of the spectral filter is between 20 nm and 100 nm.

12 . The method of claim 8 , further comprising:
removing the spectral filter.

13 . The method of claim 12 , further comprising:
applying a developer to the photoresist layer to produce a patterned layer.

14 . The method of claim 8 , wherein a diameter of the membrane is 0.5 centimeters to 3 centimeters.

15 . A method of manufacturing a semiconductor device, comprising:
forming a photoresist layer on a wafer; selecting a wavelength of an out-of-band deep ultraviolet (DUV) radiation of an extreme ultraviolet (EUV) radiation source; determining a first thickness of a spectral layer based on the selected wavelength, wherein the first thickness of the spectral layer is sufficient to reflect the selected wavelength of the DUV radiation; forming the spectral layer having the first thickness in direct contact with the photoresist layer, wherein the spectral layer comprises a polysilicon; and generating EUV radiation from the EUV radiation source, wherein the EUV radiation passes through the spectral layer and exposes the photoresist layer, the spectral layer comprises a membrane including the polysilicon deposited over a silicon nitride layer, wherein the membrane is in direct contact with the photoresist layer, and the spectral layer attenuates the DUV radiation.

16 . The method according to claim 15 , further comprising:
heating the photoresist layer in a post-application baking (PAB) operation prior to forming the spectral layer over the photoresist layer.

17 . The method of claim 15 , wherein the EUV radiation has a wavelength between 10 nm and 100 nm and the DUV radiation has a wavelength between 190 nm to 365 nm.

18 . The method of claim 15 , further comprising:
performing a post-exposure bake (PEB) after generating the EUV radiation.

19 . The method of claim 15 , further comprising:
removing the spectral layer.

20 . The method of claim 19 , further comprising:
applying a developer to the photoresist layer to produce a patterned layer over the wafer.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Shih Chih-Tsung
• Wang Chen-Ming
• Cheng Yahru
• Liu Bo-Tsun
• Lee Tsung Chuan

Classifications

• G03F7/38

  Treatment before imagewise removal, e.g. prebaking {(G03F7/265 takes precedence)} · CPC title

• G03F7/168

  Finishing the coated layer, e.g. drying, baking, soaking · CPC title

• G03F7/2004

  characterised by the use of a particular light source, e.g. fluorescent lamps or deep UV light · CPC title

• G03F7/70575

  Wavelength control, e.g. control of bandwidth, multiple wavelength, selection of wavelength or matching of optical components to wavelength · CPC title

• G03F7/70958

  Optical materials or coatings, e.g. with particular transmittance, reflectance or anti-reflection properties · CPC title