Large area high resolution feature reduction lithography technique

Patent metadata

Field	Value
Publication number	US-11042098-B2
Application number	US-201916276860-A
Country	US
Kind code	B2
Filing date	Feb 15, 2019
Priority date	Feb 15, 2019
Publication date	Jun 22, 2021
Grant date	Jun 22, 2021

Abstract

Embodiments described herein provide a method of large area lithography. One embodiment of the method includes projecting at least one incident beam to a mask in a propagation direction of the at least one incident beam. The mask having at least one period of a dispersive element that diffracts the incident beam into order mode beams having one or more diffraction orders with a highest order N greater than 1. The one or more diffraction orders provide an intensity pattern in a medium between the mask and a substrate having a photoresist layer disposed thereon. The intensity pattern includes a plurality of intensity peaks defined by sub-periodic patterns of the at least one period. The intensity peaks write a plurality of portions in the photoresist layer such that a number of the portions in the photoresist layer corresponding to the at least one period is greater than N.

First claim

What is claimed is:

1. A method, comprising:
projecting at least one incident beam to a mask in a propagation direction of the at least one incident beam, the mask having at least one period of a dispersive element, wherein:
the at least one period of the dispersive element of the mask diffracts the incident beam into a plurality of order mode beams having diffraction-orders, the diffraction orders of the order mode beams having a total of:
a highest order N greater than 1;
a negative highest order −N less than −1; and
order modes m between −N and N, the highest order N and negative highest order −N of the order mode beams each include a greater diffracted power than each of order mode beams with the orders m;

the diffraction orders provide an intensity pattern in a medium between the mask and a substrate, the order mode beams in the medium including the highest order N, the negative highest order −N, and each of the order modes m, the substrate having a photoresist layer disposed thereon;
the intensity pattern includes a plurality of intensity peaks defined by sub-periodic patterns of the at least one period; and
the intensity peaks of the sub-periodic patterns write a plurality of portions in the photoresist layer such that a number of the portions in the photoresist layer corresponding to the at least one period is greater than N.

2. The method of claim 1 , wherein:
the dispersive element is periodic in at least one of one, two, and three dimensions, quasi periodic, and aperiodic; and
the dispersive element has a feature with one of a rectangular, circular, triangular, and blazed cross section.

3. The method of claim 2 , wherein a body of the mask has a first refractive index and the dispersive element has a second refractive index different than the first refractive index.

4. The method of claim 3 , wherein a refractive material is disposed on a top surface of the dispersive element.

5. The method of claim 3 , wherein a refractive material is disposed between a surface of the body and the dispersive element.

6. The method of claim 1 , wherein the number of the portions in the photoresist layer corresponding to the at least one period is about N to about N 2 .

7. The method of claim 1 , wherein the dispersive element corresponds to at least one of a wire grid polarizer, a photonic crystal, an optical buffer, polarization splitter, a metamaterial, a flat lens, and a frequency selective filter.

8. The method of claim 1 , wherein the photoresist layer is a dual tone photoresist and the number of the portions in the photoresist layer corresponding to the at least one period is about 2N to about 2N 2 .

9. The method of claim 1 , wherein the mask comprises at least one of glass, quartz, chromium (Cr), gold (Au), silver (Ag), aluminum (Al), silicon oxycarbide (SiOC), titanium dioxide (TiO 2 ), silicon dioxide (SiO 2 ), vanadium (IV) oxide (VO x ), aluminum oxide (Al 2 O 3 ), indium tin oxide (ITO), zinc oxide (ZnO), tantalum pentoxide (Ta 2 O 5 ), silicon nitride (S i3 N 4 ), titanium nitride (TiN), and zirconium dioxide (ZrO 2 ) containing materials.

10. The method of claim 1 , wherein the number of the portions in the photoresist layer corresponding to the at least one period is between about N to about N 2 .

11. A method, comprising:
projecting at least one incident beam to a mask in a propagation direction of the at least one incident beam, the mask having at least one period of a dispersive element is disposed over a reflector, wherein:
the at least one period of the dispersive element of the mask diffracts the incident beam into a plurality of order mode beams having diffraction orders, the diffraction orders of the order mode beams having a total of:
a highest order N greater than 1;
a negative highest order −N less than −1; and
order modes m between −N and N, the highest order N and negative highest order −N of the order mode beams each include a greater diffracted power than each of order mode beams with the orders m;

the reflector reflects the order mode beams to a beam splitter that redirects the diffraction orders;
the diffraction orders provide an intensity pattern in a space between the beam splitter and a substrate, the order mode beams in the space including the highest order N, the negative highest order −N, and each of the order modes m, the substrate having a photoresist layer disposed thereon;
the intensity pattern includes a plurality of intensity peaks defined by sub-periodic patterns of the at least one period; and
the intensity peaks of the sub-periodic patterns write a plurality of portions in the photoresist layer such that a number of the portions in the photoresist layer corresponding to the at least one period is greater than N.

12. The method of claim 11 , wherein:
the dispersive element is periodic in at least one of one, two, and three dimensions, quasi periodic, and aperiodic; and
the dispersive element has a feature with one of a rectangular, circular, triangular, and blazed cross section.

13. The method of claim 12 , wherein a body of the mask has a first refractive index and the dispersive element has a second refractive index different than the first refractive index.

14. The method of claim 13 , wherein a refractive material is disposed on a top surface of the dispersive element.

15. The method of claim 13 , wherein a refractive material is disposed between a surface of the body and the dispersive element.

16. The method of claim 11 , wherein the dispersive element corresponds to at least one of a wire grid polarizer, a photonic crystal, a polarization splitter, an optical buffer, a metamaterial, a flat lens, and a frequency selective filter.

17. The method of claim 11 , wherein the photoresist layer is a dual tone photoresist and the number of the portions in the photoresist layer corresponding to the at least one period is about 2N to about 2N 2 .

18. A method, comprising:
projecting at least one incident beam to a mask in a propagation direction of the at least one incident beam, the mask having at least one period of a dispersive element, wherein:
the at least one period of the dispersive element of the mask diffracts the incident beam into a plurality of order mode beams having diffraction orders, the diffraction orders of the order mode beams having a total of:
a highest order N greater than 1;
a negative highest order −N less than −1; and
order modes m between N and N, the highest order N and negative highest order −N of the order mode beams each include a greater diffracted power than each of order mode beams with the orders m;

the mask reflects the order mode beams to a beam splitter that redirects the diffraction orders;
the diffraction orders provide an intensity pattern in a space between the beam splitter and a substrate, the order mode beams in the space including the highest order N, the negative highest order −N, and each of the order modes m, the substrate having a photoresist layer disposed thereon;
the intensity pattern includes a plurality of intensity peaks defined by sub-periodic patterns of the at least one period; and
the intensity peaks of the sub-periodic patterns write a plurality of portions in the photoresist layer such that a number of the portions in the photoresist layer corresponding to the at least one period is greater than N.

Assignees

• Applied Materials Inc

Inventors

• Chadha Arvinder

Classifications

• G03F7/7035

  Proximity or contact printers · CPC title

• G02B27/425

  in illumination systems (mask illumination systems in photolithographic systems G03F7/70158) · CPC title

• G02B5/1866

  Transmission gratings characterised by their structure, e.g. step profile, contours of substrate or grooves, pitch variations, materials (G02B5/1809, G02B5/1828, G02B5/1833, G02B5/1838 and G02B5/1847 take precedence) · CPC title

• G03F7/70408 Primary

  Interferometric lithography; Holographic lithography; Self-imaging lithography, e.g. utilizing the Talbot effect · CPC title

• G03F7/213

  Exposing with the same light pattern different positions of the same surface at the same time {(G03F7/70 takes precedence)} · CPC title