Measurement device, imprint apparatus, method for manufacturing product, light amount determination method, and light amount adjustment method

Patent metadata

Field	Value
Publication number	US-2017307367-A1
Application number	US-201715491723-A
Country	US
Kind code	A1
Filing date	Apr 19, 2017
Priority date	Apr 25, 2016
Publication date	Oct 26, 2017
Grant date	—

Abstract

A measurement device for measuring a relative position between alignment marks includes an illumination unit capable of illuminating the alignment marks at a plurality of wavelengths, a detection unit that detects light from the alignment marks, a processing unit that obtain the relative position between the alignment marks, and an adjustment unit that adjusts a relative amount between light amounts of the plurality of wavelengths so that a relative value between detection light amounts of light from the alignment marks falls within a predetermined range.

First claim

What is claimed is:

1 . A measurement device comprising:
an illumination unit for emitting light including illumination light having a first wavelength and illumination light having a second wavelength, and configured to illuminate a first alignment mark provided on the first member and a second alignment mark provided on the second member and illuminate a third alignment mark provided on the first member and a fourth alignment mark provided on the second member; a detection unit configured to detect light from the first and second alignment marks and light from the third and fourth alignment marks; a processing unit configured to obtain a relative position between the first and second alignment marks based an the detected light from the first and second alignment marks, and a relative position between the third and fourth alignment marks based on the detected light from the third and fourth alignment marks; and an adjustment unit configured to adjust a relative amount between a light amount of illumination light having the first wavelength and a light amount of illumination light having the second wavelength so that a relative value between a detection light amount of the light from the first and second alignment marks detected by the detection unit and a detection light amount of the from the third and fourth alignment marks detected by the detection unit falls within a predetermined range.

2 . The measurement device according to claim 1 ,
wherein the adjustment unit includes a changing unit configured to change output energy of a first light source configured to emit the illumination light having the first wavelength and a second light source configured to emit the illumination light having the second wavelength, and wherein the adjustment unit is configured to control the changing unit to adjust a relative amount between a light amount of the illumination light having the first wavelength emitted from the first light source and a light amount of the illumination light having the second wavelength emitted from the second light source.

3 . The measurement device according to claim 1 , wherein the adjustment unit is configured to adjust the relative amount between the light amount of illumination light having the first wavelength and the light amount of illumination light having the second wavelength so that a relative value between a detection light amount of the light from the third alignment mark and a detection light amount of the light from the fourth alignment mark detected by the detection unit falls within a predetermined range.

4 . The measurement device according to claim 1 ,
wherein the detection unit includes an image sensor configured to obtain an image of an alignment mark, and wherein an image of the first, second, third, and fourth alignment marks is obtained by an imaging plane of the image sensor.

5 . The measurement device according to claim wherein measurement accuracy of the relative position between the first and second alignment marks obtained by detecting the light from the first and second alignment marks is higher than that of the relative position between the third and fourth alignment marks obtained by detecting the light from the third and fourth alignment marks.

6 . The measurement device according to claim wherein the first alignment mark is a first diffraction grating having a period in both a first direction and a second direction, and the second alignment mark is a second diffraction grating having a period in the second direction, the period of the second diffraction grating being different from that of the first diffraction grating in the second direction.

7 . The measurement device according to claim 6 ,
wherein the detection unit includes an image sensor configured to obtain an image of an alignment mark, and wherein the image sensor is configured to obtain an image of a moiré pattern produced by the first and second diffraction gratings, an image of the third alignment mark, and an image of the fourth alignment mark.

8 . The measurement device according to claim 7 , wherein the adjustment unit is configured to adjust the relative amount between the light amount of illumination light having the first wavelength and the light amount of illumination light having the second wavelength so that a detection light amount of light from an end of the first and second diffraction gratings detected by the detection unit is smaller than twice a detection light amount of light from a central part of the first and second diffraction gratings.

9 . The measurement device according to claim further comprising a control unit configured to determine a target light amount of the illumination light having the first wavelength and a target light amount of the illumination light having the second wavelength so that the relative value between the detection light amount of the light from the first and second alignment marks and the detection light amount of the light from the third and fourth alignment marks detected by the detection unit falls within the predetermined range, and
wherein the adjustment unit is configured to adjust a light amount of the illumination light having the first wavelength and a light amount of the illumination light having the second wavelength to the determined respective target light amounts.

10 . The measurement device according to claim 1 , wherein the adjustment unit is configured to adjust the relative amount between the light amount of illumination light having the first wavelength and the light amount of illumination light having the second wavelength so that the detection light amount of the light from the first and second alignment marks and the detection light amount of the light from the third and fourth alignment marks detected by the detection unit are greater than or equal to 40% of a maximum light amount detectable by the detection unit.

11 . A measurement device comprising:
an illumination unit for emitting illumination light having a first wavelength and illumination light having a second wavelength shorter than the first wavelength, and configured to illuminate a first diffraction grating provided on a first member and a second diffraction grating provided on a second member, the first diffraction grating having a period in both a first direction and a second direction, the second diffraction grating having a period in the second direction, the period of the second diffraction grating being different from that of the first diffraction grating in the second direction, and illuminate a third alignment mark provided on the first member and a fourth alignment mark provided on the second member; a detection unit configured to detect light having the first wavelength from the first and second diffraction gratings and light having the second wavelength from the third and fourth alignment marks, the first to fourth alignment marks being illuminated by the illumination unit; and a processing unit configured to obtain a relative position between the first and second diffraction gratings based on the light having the first wavelength from the first and second diffraction gratings, and obtain a relative position between the third and fourth alignment marks based on the light having the second wavelength from the third and fourth alignment marks.

12 . An imprint apparatus for forming a pattern on an imprint material on a substrate by using a mold, the imprint apparatus comprising:
the measurement device according to claim configured to measure a relative position between an alignment mark provided on the substrate and an alignment mark provided on the mold; and an alignment unit configured to align the subs

Assignees

• Canon Kk

Inventors

• Yaegashi Kenji
• Iwai Toshiki
• Komaki Takamitsu

Classifications

• G03F7/0002

  Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping · CPC title

• G03F9/7023

  Aligning or positioning in direction perpendicular to substrate surface · CPC title

• G02B27/60

  Systems using moiré fringes · CPC title

• G03F9/7042

  Alignment for lithographic apparatus using patterning methods other than those involving the exposure to radiation, e.g. by stamping or imprinting (non-exposure lithographic processes per se G03F7/0002) · CPC title

• G03F9/7088 Primary

  Alignment mark detection, e.g. TTR, TTL, off-axis detection, array detector, video detection · CPC title