Process for designing and checking a mask layout

• US 5,801,954 A
• Filed: 04/24/1996
• Issued: 09/01/1998
• Est. Priority Date: 04/24/1996
• Status: Expired due to Term

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Pierrat, Christophe, Le, Chin Aik
• Primary Examiner(s): Voeltz, Emanuel Todd
• Assistant Examiner(s): GARBOWSKI, LEIGH M
• Application Number:
  US08/637,307
• Time in Patent Office: 860 Days
• Field of Search: 364/488, 364/489, 364/490, 364/491, 382/144, 430/5
• US Class Current: 716/52
• CPC Class Codes: G01N 2021/95676 Masks, reticles, shadow masks
• CPC Class Codes: G01N 21/956 Inspecting patterns on the surface of objects contactless testing of electronic circuits G01R31/308; testing currency G07D; manufacturing processes per se of semiconductor devices implementing a measuring step H01L22/10
• CPC Class Codes: G03F 1/26 Phase shift masks [PSM]; PSM blanks; Preparation thereof
• 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

Abstract

A process for designing and checking a mask layout is provided. A mask layout is generated from a binary mask layout design. An aerial image of the mask layout is then calculated using simulation software. The simulated aerial image is then compared to the binary mask layout design and modifications are made to the mask layout if necessary.

Claims

1. A process for checking a mask layout comprising:

obtaining a binary mask layout design;

generating a phase shifting mask layout having multiple layers that are printed using a voting technique to correspond to said binary mask layout design;

calculating an aerial image of said mask layout using simulation software; and

comparing said aerial image to said binary mask layout design.

2. A process for checking a mask layout as defined in claim 1 wherein said aerial image is calculated and compared at both best focus and best focus ±

a focus margin.

3. A process for checking a mask layout as defined in claim 1 wherein said aerial image is compared to said binary mask layout design using a design rule checker.

4. A process for checking a mask layout as defined in claim 1 further comprising generating a modified mask layout to correspond to said binary mask layout design if said comparison of said aerial image to said binary mask layout design does not fall with predetermined design rules.

5. A process for designing a mask layout comprising:

obtaining a binary mask layout design;

generating a phase shifting mask layout having multiple layers that are printed using a voting technique to correspond to said binary mask layout design;

calculating an aerial image of said mask layout using simulation software;

comparing said aerial image to said binary mask layout design using a design rule checker; and

modifying said mask layout to more closely correspond to said binary mask layout design if said comparison of said aerial image to said binary mask layout design does not fall within predetermined design rules.

6. A process for designing a mask layout as defined in claim 5 wherein said aerial image is calculated and compared at both best focus and best focus ±

a focus margin.