Method for making correction map of dose amount, exposure method, and method for manufacturing semiconductor device

• US 8,832,607 B2
• Filed: 08/30/2012
• Issued: 09/09/2014
• Est. Priority Date: 03/22/2012
• Status: Active Grant

• Current Assignee: Kioxia Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Mizuno, Hiroyuki, Okamoto, Yosuke, Koike, Takashi
• Primary Examiner(s): Siek, Vuthe
• Application Number:
  US13/598,736
• Publication Number:
  US 20130252176A1
• Time in Patent Office: 740 Days
• Field of Search: 716/51, 430/315, 430/319
• US Class Current: 716/51
• CPC Class Codes: G03F 1/36 Masks having proximity correction features; Preparation thereof, e.g. optical proximity correction [OPC] design processes
• CPC Class Codes: G03F 7/2002 with visible light or UV light, through an original having an opaque pattern on a transparent support, e.g. film printing, projection printing; by reflection of visible or UV light from an original such as a printed image
• CPC Class Codes: G03F 7/705 Modelling or simulating from physical phenomena up to complete wafer processes or whole workflow in wafer productions
• CPC Class Codes: G03F 7/70558 Dose control, i.e. achievement of a desired dose
• CPC Class Codes: G03F 7/70941 Stray fields and charges, e.g. stray light, scattered light, flare, transmission loss
• 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

Abstract

According to one embodiment, a method for making a correction map of a dose amount of EUV light used when exposing with the EUV light, includes estimating an exposure result based on an initial correction map of the dose amount and flare of the EUV light, determining a goodness of the exposure result, and correcting the initial correction map in the case where the exposure result is unacceptable. And, the correcting of the initial correction map, the estimating of the exposure result, and the determining of the goodness are repeated until the exposure result is good.

Claims

1. A method for making a correction map of a dose amount, the dose amount being a dose amount of EUV light used when exposing with the EUV light, the exposing being performed by sequentially irradiating the EUV light onto a plurality of regions, the method comprising:

making an initial correction map of the dose amount by considering at least one selected from the group consisting of a nonuniformity of a dose amount of EUV light emitted from a light source, a bias of a pattern of an EUV mask, and fluctuation of exposing by an exposure apparatus, but not considering a flare of the EUV light;

calculating, using a processor programmed to perform the calculating, an aerial image of the EUV mask to be optically formed at a position of a resist film based on the initial correction map of the dose amount and flare irradiated onto one of the regions when the EUV light is irradiated onto the one of the regions;

estimating a pattern formed in the resist film by performing a simulation of the exposing and a developing based on the aerial image;

determining whether or not all of differences between estimated values and target values of critical dimensions of portions of the estimated pattern are less than reference values; and

correcting the initial correction map in the case where at least one of the differences is more than the reference value,

the correcting of the initial correction map, the calculating of the aerial image, the estimating of the pattern, and the determining being repeated until all of the differences are less than the reference value.

2. The method according to claim 1, further comprising correcting the initial correction map based on flare irradiated onto the one of the regions when the EUV light is irradiated onto one other region of the plurality of regions after all of the differences become less than the reference value.

3. The method according to claim 2, wherein a configuration of each of the regions is a rectangle, and the one other region is a region contacting the one of the regions.

4. The method according to claim 2, wherein a configuration of each of the regions is a rectangle, and the one other region includes a region contacting the one of the regions and a region disposed at a diagonal position as viewed from the one of the regions.

5. The method according to claim 2, wherein the correcting of the initial correction map based on the flare irradiated onto the one of the regions when the EUV light is irradiated onto the one other region includes pre-classifying the plurality of regions into a plurality of groups based on a disposition of the one other region with respect to the one of the regions and includes considering the flare according to the group of the one of the regions.

6. A method for making a correction map of a dose amount, the dose amount being a dose amount of EUV light used when exposing with the EUV light, the exposing being performed by sequentially irradiating the EUV light onto a plurality of regions, the method comprising:

making an initial correction map of the dose amount by considering at least one selected from the group consisting of a nonuniformity of a dose amount of EUV light emitted from a light source, a bias of a pattern of an EUV mask, and fluctuation of exposing by an exposure apparatus, but not considering a flare of the EUV light;

calculating, using a processor programmed to perform the calculating, an aerial image of the EUV mask to be optically formed at a position of a resist film based on the initial correction map of the dose amount and both flare irradiated onto one of the regions when the EUV light is irradiated onto the one of the regions and flare irradiated onto the one of the regions when the EUV light is irradiated onto one other region of the plurality of regions;

estimating a pattern formed in the resist film by performing a simulation of the exposing and a developing based on the aerial image;

determining whether or not all of differences between estimated values and target values of critical dimensions of portions of the estimated pattern are less than reference values; and

correcting the initial correction map in the case where at least one of the differences is more than the reference value,

the correcting of the initial correction map, the calculating of the aerial image, the estimating of the pattern, and the determining being repeated until all of the differences are less than the reference value.

7. The method according to claim 6, wherein a configuration of each of the regions is a rectangle, and the one other region is a region contacting the one of the regions.

8. The method according to claim 6, wherein a configuration of each of the regions is a rectangle, and the one other region includes a region contacting the one of the regions and a region disposed at a diagonal position as viewed from the one of the regions.

9. The method according to claim 6, wherein

the calculating of the aerial image includes pre-classifying the plurality of regions into a plurality of groups based on a disposition of the one other region with respect to the one of the regions and includes considering the flare according to the group of the one of the regions.

10. An exposure method including correcting a dose amount and irradiating EUV light based on a correction map of the dose amount,

the exposing being performed by sequentially irradiating the EUV light onto a plurality of regions,

the correction map being made by:

making an initial correction map of the dose amount by considering at least one selected from the group consisting of a nonuniformity of a dose amount of EUV light emitted from a light source, a bias of a pattern of an EUV mask, and fluctuation of exposing by an exposure apparatus, but not considering a flare of the EUV light;

calculating, using a processor programmed to perform the calculating, an aerial image of the EUV mask to be optically formed at a position of a resist film based on the initial correction map of the dose amount and flare irradiated onto one of the regions when the EUV light is irradiated onto at least the one of the regions;

estimating a pattern formed in the resist film by performing a simulation of the exposing and a developing based on the aerial image;

determining whether or not all of differences between estimated values and target values of critical dimensions of portions of the estimated pattern are less than reference values; and

correcting the initial correction map in the case where at least one of the differences is more than the reference value,

repeating the correcting of the initial correction map, the calculating of the aerial image, the estimating of the pattern, and the determining until all of the differences are less than the reference value.

11. A method for manufacturing a semiconductor device, comprising:

forming a resist film above a semiconductor substrate;

exposing the resist film;

forming a resist pattern by developing the resist film; and

performing processing of the semiconductor substrate using the resist pattern as a mask,

the exposing of the resist film being performed by sequentially irradiating EUV light onto a plurality of regions and correcting a dose amount based on a correction map of the dose amount,

the correction map being made by;

making an initial correction map of the dose amount by considering at least one selected from the group consisting of a nonuniformity of a dose amount of EUV light emitted from a light source, a bias of a pattern of an EUV mask, and fluctuation of exposing by an exposure apparatus, but not considering a flare of the EUV light;

calculating, using a processor programmed to perform the calculating, an aerial image of the EUV mask to be optically formed at a position of a resist film based on the initial correction map of the dose amount and flare irradiated onto one of the regions when the EUV light is irradiated onto at least the one of the regions;

estimating a pattern formed in the resist film by performing a simulation of the exposing and a developing based on the aerial image;

determining whether or not all of differences between estimated values and target values of critical dimensions of portions of the estimated pattern are less than reference values; and

correcting the initial correction map in the case where at least one of the differences is more than the reference value,

repeating the correcting of the initial correction map, the calculating of the aerial image, the estimating of the pattern, and the determining until all of the differences are less than the reference value.

12. The method according to claim 11, wherein the initial correction map is corrected further based on flare irradiated onto the one of the regions when the EUV light is irradiated onto one other region of the plurality of regions after all of the differences become less than the reference value.

13. The method according to claim 12, wherein a configuration of each of the regions is a rectangle, and the one other region is a region contacting the one of the regions.

14. The method according to claim 12, wherein a configuration of each of the regions is a rectangle, and the one other region includes a region contacting the one of the regions and a region disposed at a diagonal position as viewed from the one of the regions.

15. A method for manufacturing a semiconductor device, comprising:

forming a resist film above a semiconductor substrate;

exposing the resist film;

forming a resist pattern by developing the resist film; and

performing processing of the semiconductor substrate using the resist pattern as a mask,

the exposing of the resist film being performed by sequentially irradiating EUV light onto a plurality of regions and correcting a dose amount based on a correction map of the dose amount,

the correction map being made by;

making an initial correction map of the dose amount by considering at least one selected from the group consisting of a nonuniformity of a dose amount of EUV light emitted from a light source, a bias of a pattern of an EUV mask, and fluctuation of exposing by an exposure apparatus, but not considering a flare of the EUV light;

calculating, using a processor programmed to perform the calculating, an aerial image of the EUV mask to be optically formed at a position of a resist film based on the initial correction map of the dose amount and both flare irradiated onto one of the regions when the EUV light is irradiated onto the one of the regions and flare irradiated onto the one of the regions when the EUV light is irradiated onto one other region of the plurality of regions;

estimating a pattern formed in the resist film by performing a simulation of the exposing and a developing based on the aerial image;

determining whether or not all of differences between estimated values and target values of critical dimensions of portions of the estimated pattern are less than reference values; and

correcting the initial correction map in the case where at least one of the differences is more than the reference value,

repeating the correcting of the initial correction map, the calculating of the aerial image, the estimating of the pattern, and the determining until all of the differences are less than the reference value.