Generating method of drawing data and charged particle beam drawing method

• US 10,445,450 B2
• Filed: 08/31/2017
• Issued: 10/15/2019
• Est. Priority Date: 09/01/2016
• Status: Active Grant

• Current Assignee: NuFlare Technology, Inc. (Toshiba Corporation)
• Original Assignee: NuFlare Technology, Inc. (Toshiba Corporation)
• Inventors: Hara, Shigehiro, Yasui, Kenichi
• Primary Examiner(s): Siek, Vuthe
• Application Number:
  US15/691,951
• Publication Number:
  US 20180060474A1
• Time in Patent Office: 775 Days
• CPC Class Codes: G03F 1/78 by charged particle beam [CPB], e.g. electron beam patterning of masks
• CPC Class Codes: G06F 30/30 Circuit design
• CPC Class Codes: G06V 10/507 Summing image-intensity values; Histogram projection analysis
• CPC Class Codes: H01J 2237/31762 Computer and memory organisation
• CPC Class Codes: H01J 2237/31764 Dividing into sub-patterns
• CPC Class Codes: H01J 37/3026 Patterning strategy
• CPC Class Codes: H01J 37/3177 Multi-beam, e.g. fly's eye, comb probe

Abstract

In one embodiment, a generating method of drawing data includes generating a pixel map that includes dose amount information on each of pixels obtained by dividing a drawing area on an object into a mesh, extracting, from the pixel map, an island-shaped pixel map which is a group of multiple pixels in which the dose amount information is not zero, determining an order of definition of the dose amount information on the pixels in the island-shaped pixel map, and generating a compressed pixel map including a size of the pixels, information indicating the order of definition, coordinates of a pixel which is first in the order of definition in the island-shaped pixel map, and the dose amount information on the pixels in the island-shaped pixel map, the dose amount information being continuously defined based on the order of definition.

Claims

1. A pixel map compressing method comprising:

generating a pixel map that includes dose amount information on each of pixels obtained by dividing a drawing area on a substrate into a mesh, the substrate being a target on which drawing is performed by a charged particle beam drawing apparatus;

extracting, from the pixel map, an island-shaped pixel map which is a group of multiple pixels in which the dose amount information is not zero;

determining an order of definition of the dose amount information on the pixels in the island-shaped pixel map based on a shape of the island-shaped pixel map; and

generating a compressed pixel map including a size of the pixels, information indicating the order of definition, coordinates of a pixel which is first in the order of definition in the island-shaped pixel map, and the dose amount information on the pixels in the island-shaped pixel map, the dose amount information being continuously defined based on the order of definition.

2. The method according to claim 1,

wherein the pixel map is generated based on design data based on a layout drawn on the substrate and a correction condition parameter.

3. The method according to claim 1,

wherein to the island-shaped pixel map, the pixels on nth column (n is an integer greater than or equal to 1) are sequentially defined in a first direction, and the pixels on (n+1)th column are sequentially defined in a second direction opposite to the first direction.

4. The method according to claim 3,

wherein a pixel which is first in the order of definition on the (n+1)th column is set to an inflection point pixel, and

the dose amount information on each of the pixels in the compression pixel map includes a header section that indicates whether or not the pixel is the inflection point pixel.

5. The method according to claim 4,

wherein a position of a pixel which is last in the order of definition on the nth column, and a position of the pixel which is first in the order of definition on the (n+1)th column are same or displaced by one pixel in the first direction.

6. The method according to claim 5,

wherein when the position of the pixel which is last in the order of definition on the nth column and the position of the pixel which is first in the order of definition on the (n+1)th column are displaced by two or more pixels in the first direction, a null pixel is added to the nth column to cause the displacement to be one pixel, and the compressed pixel map is generated.

7. The method according to claim 3,

wherein when an intermediate pixel on the nth column is missing, a null pixel is added to fill a missing portion, and the compressed pixel map is generated.

8. The method according to claim 1,

wherein a group consisting of multiple pixels in which the dose amount information is not zero is divided into a first island-shaped pixel map and a second island-shaped pixel map,

in the first island-shaped pixel map, the dose amount information on the pixels is sequentially defined in a first direction or in a second direction opposite to the first direction, and

in the second island-shaped pixel map, the dose amount information on the pixels is sequentially defined in a third direction perpendicular to the first direction or in a fourth direction opposite to the third direction.

9. The method according to claim 1,

wherein the dose amount information is converted to representation of a difference from dose amount information on a pixel which is preceding in the order of definition, and the compressed pixel map is generated.

10. A charged particle beam drawing method comprising:

generating a pixel map that includes dose amount information on each of pixels obtained by dividing a drawing area on a substrate into a mesh, the substrate being a target on which drawing is performed by a charged particle beam drawing apparatus;

extracting, from the pixel map, an island-shaped pixel map which is a group of multiple pixels in which the close amount information is not zero;

determining an order of definition of the dose amount information on the pixels in the island-shaped pixel map based on a shape of the island-shaped pixel map;

generating a compressed pixel map including a size of the pixels, information indicating the order of definition, coordinates of a pixel which is first in the order of definition in the island-shaped pixel map, and the dose amount information on the pixels in the island-shaped pixel map, the dose amount information being continuously defined based on the order of definition;

transferring the compressed pixel map to the charged particle beam drawing apparatus; and

drawing a figure pattern by irradiating the substrate with a charged particle beam based on a dose amount which is calculated in a following manner;

the compressed pixel map is expanded and the dose amount per mesh area having a predetermined size is calculated by the charged particle beam drawing apparatus.