Mask data creation method

• US 7,569,312 B2
• Filed: 11/20/2006
• Issued: 08/04/2009
• Est. Priority Date: 02/17/2003
• Status: Expired due to Fees

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Misaka, Akio
• Primary Examiner(s): ROSASCO, STEPHEN D
• Application Number:
  US11/601,705
• Publication Number:
  US 20070141479A1
• Time in Patent Office: 988 Days
• Field of Search: 430/5, 430/311, 430/322, 430/394, 716/19, 716/20, 716/21
• US Class Current: 430/5
• CPC Class Codes: G03F 1/26 Phase shift masks [PSM]; PSM blanks; Preparation thereof
• CPC Class Codes: G03F 1/32 Attenuating PSM [att-PSM], e.g. halftone PSM or PSM having semi-transparent phase shift portion,; Preparation thereof
• CPC Class Codes: G03F 1/36 Masks having proximity correction features; Preparation thereof, e.g. optical proximity correction [OPC] design processes

Abstract

A mask pattern includes a main pattern to be transferred through exposure and an auxiliary pattern that diffracts exposing light and is not transferred through the exposure. The main pattern is made from a shielding portion, a phase shifter or a combination of a semi-shielding portion or a shielding portion and a phase shifter. The auxiliary pattern is made from a shielding portion or a semi-shielding portion. The auxiliary pattern is disposed in a position away from the main pattern by a distance M×(λ/(2×sin φ)) or M×((λ/(2×sin φ))+(λ/(NA+sin φ))), wherein λ indicates a wavelength of the exposing light, M and NA indicate magnification and numerical aperture of a reduction projection optical system of an aligner and φ indicates an oblique incident angle.

Claims

1. A mask data creation method for creating mask data for a photomask including a mask pattern formed on a transparent substrate and a transparent portion of said transparent substrate where said mask pattern is not formed, comprising the steps of:

(a) generating a main pattern corresponding to a desired unexposed region of a resist formed by irradiating said resist with exposing light through said photomask;

(b) determining a shape of a phase shifter that is disposed within said main pattern and transmits said exposing light in an opposite phase with respect to said transparent portion;

(c) disposing an auxiliary pattern for diffracting said exposing light in a position on said transparent substrate away from said phase shifter by a given distance;

(d) setting an edge of said main pattern corresponding to a boundary between said main pattern and said transparent portion as a CD adjustment edge;

(e) predicting, through simulation, a dimension of a resist pattern formed by using said main pattern including said phase shifter and said auxiliary pattern; and

(f) changing a shape of said main pattern by moving said CD adjustment edge when said predicted dimension of said resist pattern does not accord with a desired dimension.

2. The mask data creation method of claim 1,

wherein said main pattern includes a semi-shielding portion that transmits said exposing light in an identical phase with respect to said transparent portion.

3. The mask data creation method of claim 2,

wherein said phase shifter is disposed at a center of a part having a given or smaller dimension of said main pattern to be surrounded by said semi-shielding portion.

4. The mask data creation method of claim 2,

wherein said phase shifter is disposed with a part of said semi-shielding portion having a given or larger width sandwiched between said transparent portion and said phase shifter.

5. The mask data creation method of claim 2,

wherein said phase shifter is disposed in a peripheral portion of said main pattern.

6. The mask data creation method of claim 1,

wherein said main pattern includes a shielding portion, and

said phase shifter is disposed at a center of a part having a given or smaller dimension of said main pattern to be surrounded by said shielding portion.

7. The mask data creation method of claim 6,

wherein said phase shifter is disposed with a part of said shielding portion having a given or larger width sandwiched between said transparent portion and said phase shifter.

8. The mask data creation method of claim 1, wherein said step (c) comprises the sub-steps of:

(c1) separating said main pattern into a first region and a second region;

(c2) disposing a first auxiliary pattern, which is to be a part of said auxiliary pattern, for diffracting said exposing light in a position on said transparent substrate away from said first region of said main pattern by a given distance; and

(c3) disposing a second auxiliary pattern, which is to be a part of said auxiliary pattern, for diffracting said exposing light in a position on said transparent substrate away from said second region of said main pattern by another given distance.

9. The mask data creation method of claim 8,

wherein either of said first region and said second region is a transistor region.