Multi charged particle beam writing apparatus, and multi charged particle beam writing method

Patent metadata

Field	Value
Publication number	US-9287090-B2
Application number	US-201414556503-A
Country	US
Kind code	B2
Filing date	Dec 1, 2014
Priority date	Dec 4, 2013
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

A multi charged particle beam writing apparatus includes a divided shot data generation unit to generate, for each shot of multi beams of charged particle beams, data for plural times of divided shots such that irradiation for one shot of each beam is divided into plural times of divided shots each having a different irradiation time, an individual blanking system to provide blanking control individually for each of multi beams, based on the data for plural times of divided shots, an elastic rate correction value acquisition unit to acquire, for each of plural times of divided shots, an elastic rate correction value for correcting an elastic rate of an image of the whole multi beams, depending upon the number of ON-beams of the multi beams, and a lens to correct, for each divided shot, the elastic rate of the image of the whole multi beams by using the correction value.

First claim

What is claimed is:

1. A multi charged particle beam writing apparatus comprising:
a divided shot data generation unit configured to generate, for each shot of multi beams of charged particle beams, data for a plurality of times of divided shots such that irradiation for one shot of each beam is divided into the plurality of times of divided shots each having a different irradiation time;
an individual blanking system configured to provide blanking control individually for the each beam of the multi beams, based on the data for the plurality of times of divided shots;
an elastic rate correction value acquisition unit configured to acquire, for each divided shot of the plurality of times of divided shots, a correction value for correcting a position deviation of a writing pattern, depending upon a number of ON beams of the multi beams; and
a lens configured to correct, for the each divided shot, the position deviation of the writing pattern by using the correction value.

2. The apparatus according to claim 1 further comprising:
a center position correction value acquisition unit configured to acquire, for the each divided shot, a center position correction value for correcting a beam center position of the whole of the multi beams; and
a deflector configured to correct, for the each divided shot, the beam center position of the whole of the multi beams by using the center position correction value.

3. The apparatus according to claim 1 further comprising:
a focus position correction value acquisition unit configured to acquire, for the each divided shot, a focus position correction value for correcting a focus position of the whole of the multi beams; and
a second lens configured to correct, for the each divided shot, the focus position of the whole of the multi beams by using the focus position correction value.

4. The apparatus according to claim 1 further comprising:
a common blanking system configured to perform, for the each divided shot, beam ON/OFF control collectively for the whole of the multi beams, in addition to beam ON/OFF switching performed for the each beam by the individual blanking system.

5. The apparatus according to claim 1 further comprising:
an irradiation time calculation unit configured to calculate, for each mesh region of a predetermined size, an irradiation time per shot of the each beam of the multi beams.

6. The apparatus according to claim 5 further comprising:
a gray level value calculation unit configured to calculate a gray level value of an integer used in defining the irradiation time for the each mesh region by using a predetermined quantization unit.

7. The apparatus according to claim 6 , wherein the divided shot data generation unit converts the gray level value into n binary numbers previously set, where the n is a number of digits.

8. The apparatus according to claim 7 , wherein the divided shot data generation unit divides the irradiation of the one shot of the each beam into n divided shots, where the n is the number of digits.

9. The apparatus according to claim 8 , wherein, as irradiation time of the plurality of times of divided shots, an irradiation time equivalent to what is obtained by defining each value of the n binary numbers in decimal notation is used, where the n is the number of digits.

10. A multi charged particle beam writing method comprising:
dividing, for each shot of multi beams of charged particle beams, irradiation for one shot of each beam of the multi beams into a plurality of times of divided shots each having a different irradiation time, and irradiating, in order, a beam of an irradiation time corresponding to each of the plurality of times of divided shots onto a target object; and
correcting, for the each of the plurality of times of divided shots, a position deviation of a writing pattern, depending upon a number of ON beams of the multi beams.

11. A multi charged particle beam writing apparatus comprising:
a divided shot data generation means for generating, for each shot of multi beams of charged particle beams, data for a plurality of times of divided shots such that irradiation for one shot of each beam is divided into the plurality of times of divided shots each having a different irradiation time;
an individual blanking means for providing blanking control individually for the each beam of the multi beams, based on the data for the plurality of times of divided shots;
an elastic rate correction value acquisition means for acquiring, for each divided shot of the plurality of times of divided shots, a correction value for correcting a position deviation of a writing pattern, depending upon a number of ON beams of the multi beams; and
a lens for correcting, for the each divided shot, the position deviation of the writing pattern by using the correction value.

Assignees

• Nuflare Technology Inc

Inventors

• Yoshikawa Ryoichi
• Matsumoto Hiroshi

Classifications

• H01J37/3023

  Program control · CPC title

• H01J2237/0437

  Semiconductor substrate · CPC title

• H01J37/3177 Primary

  Multi-beam, e.g. fly's eye, comb probe · CPC title

• H01J37/243

  Beam current control or regulation circuits (H01J37/241 takes precedence) · CPC title

• H01J37/045

  Beam blanking or chopping, i.e. arrangements for momentarily interrupting exposure to the discharge · CPC title