Method for forming circular patterns on a surface

• US 9,268,214 B2
• Filed: 11/24/2014
• Issued: 02/23/2016
• Est. Priority Date: 09/01/2008
• Status: Active Grant

• Current Assignee: D2S, Inc.
• Original Assignee: D2S, Inc.
• Inventors: Fujimura, Akira, Tucker, Michael
• Primary Examiner(s): YOUNG, CHRISTOPHER G
• Application Number:
  US14/552,360
• Publication Number:
  US 20150082258A1
• Time in Patent Office: 456 Days
• Field of Search: 430/5, 430/30, 430/296, 430/396, 430/942, 716/53, 716/55
• US Class Current: 1/1
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: G03F 1/20 Masks or mask blanks for imaging by charged particle beam [CPB] radiation, e.g. by electron beam; Preparation thereof
• CPC Class Codes: G03F 1/70 Adapting basic layout or design of masks to lithographic process requirements, e.g., second iteration correction of mask patterns for imaging
• CPC Class Codes: G03F 1/78 by charged particle beam [CPB], e.g. electron beam patterning of masks
• CPC Class Codes: G03F 7/20 Exposure; Apparatus therefor photographic printing apparatus for making copies G03B27/00
• CPC Class Codes: G03F 7/2037 Exposure with X-ray radiation or corpuscular radiation, through a mask with a pattern opaque to that radiation
• CPC Class Codes: G03F 7/2063 for the production of exposure masks or reticles
• CPC Class Codes: G03F 7/7025 Size or form of projection system aperture, e.g. aperture stops, diaphragms or pupil obscuration; Control thereof
• CPC Class Codes: G06F 2119/06 Power analysis or power optimisation
• CPC Class Codes: G06F 2119/18 Manufacturability analysis or optimisation for manufacturability
• CPC Class Codes: G06F 30/00 Computer-aided design [CAD]
• CPC Class Codes: G06F 30/39 Circuit design at the physical level physical level design for reconfigurable circuits G06F30/347
• CPC Class Codes: G06F 30/398 Design verification or optimisation, e.g. using design rule check [DRC], layout versus schematics [LVS] or finite element methods [FEM] optical proximity correction [OPC] design processes G03F1/36
• CPC Class Codes: H01J 37/3174 Particle-beam lithography, e.g. electron beam lithography
• CPC Class Codes: Y10S 430/143 Electron beam

Abstract

A method for fracturing or mask data preparation is disclosed, in which a set of shots is determined, where each shot will direct a circular or nearly-circular dosage pattern to a surface, where each shot comprises a shot dosage, and in which the set of shots is output. A method for forming patterns on a surface using charged particle beam lithography is also disclosed, in which a stencil is provided comprising one or more circular apertures, and where a plurality of circular patterns of different sizes are formed on the surface using a single aperture, by varying the shot dosage.

Claims

1. A method for fracturing or mask data preparation for charged particle beam lithography, the method comprising:

determining a set of shots, wherein each shot will direct a circular or nearly-circular dosage pattern to a surface, and wherein each shot comprises a shot dosage; and

outputting the set of shots, wherein the shot dosages vary;

wherein the determining is performed using a computing hardware device.

2. The method of claim 1 wherein the determining comprises calculating a pattern that will be formed on the surface.

3. The method of claim 2 wherein the calculating comprises charged particle beam simulation.

4. The method of claim 3 wherein the charged particle beam simulation includes at least one of a group consisting of forward scattering, resist diffusion, Coulomb effect, backward scattering, loading, fogging, and etch.

5. The method of claim 1 wherein the surface comprises a reticle.

6. The method of claim 1 wherein the surface comprises a semiconductor wafer.

7. A method for forming a plurality of circular patterns on a surface comprising:

providing a charged particle beam source;

providing a stencil containing a circular aperture, through which the charged particle beam source may be shot; and

forming a plurality of circular patterns of different sizes on the surface using a single aperture, by varying the shot dosage.

8. The method of claim 7 further comprising using charged particle beam simulation to calculate the size of each of the plurality of circular patterns before forming them on the surface.

9. The method of claim 8 wherein the charged particle beam simulation includes at least one of the group consisting of forward scattering, backward scattering, resist diffusion, Coulomb effect, etching, fogging, loading and resist charging.

10. The method of claim 7 wherein the stencil contains a plurality of circular apertures.

11. The method of claim 7 wherein the surface comprises a reticle.

12. The method of claim 7 wherein the surface comprises a semiconductor wafer.