IP Library › Granted Patent US 7,172,841
Granted Patent B2
US 7,172,841 · App. 10/734,248 · Granted Feb 6, 2007

Crystallization apparatus, crystallization method, and phase shift mask

Assignee: Advanced LCD Technologies Development Center Co., Ltd.
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Quick Facts
Patent No.
US 7,172,841
App. No.
10/734,248
Granted
Feb 6, 2007
Kind
B2
Abstract

A phase shift mask is arranged before a laser device through a beam expander, a homogenizer and a mirror, and a processed substrate is set on an opposed surface of the phase shift mask with an image forming optical system therebetween. The processed substrate is held at a predetermined position by using a substrate chuck such as a vacuum chuck or an electrostatic chuck.

Claims (26)

1. A crystallization apparatus comprising:

a light source which emits a light beam;

a mask which receives the light beam from the light source and makes an intensity distribution of the light beam into an inverse peak pattern that a peak value has a minimum intensity; and

an image forming optical system which is positioned between the mask and a processed substrate, and forms an image of the light beam having the inverse peak pattern on the processed substrate, thereby crystallizing at least a part of a substance of the processed substrate.

2. The crystallization apparatus according to claim 1 , wherein the mask has a phase shift mask in which adjacent areas have different thicknesses and a phase shift portion having a step between these areas is defined.

3. The crystallization apparatus according to claim 2 , wherein the a phase difference of the phase shift portion of the mask is 180° so as to produce a peak value of which the intensity is substantially zero.

4. The crystallization apparatus according to claim 1 , further comprising a support which supports the processed substrate at a defocus position separated from a focal position of the image forming optical system by a predetermined distance.

5. The crystallization apparatus according to claim 1 , further comprising a support which supports the processed substrate at a focal position of the image forming optical system, wherein the image forming optical system has an aperture whose NA can be changed so as to be capable of adjusting a width of the inverse peak pattern.

6. The crystallization apparatus according to claim 5 , wherein assuming that λ is a wavelength of the light beam and NA is a numerical aperture of the aperture, a width D of the inverse peak pattern is given by the following expression:

D=kλ/NA ( k is a value from 0.5 to 2).

7. The crystallization apparatus according to claim 1 , further comprising a support which supports the processed substrate at a focal position of the image forming optical system, wherein the image forming optical system has a pupil which sets a two-stage peak pattern having a first pattern positioned on a side where an intensity is low that an inverse peak pattern has a peak value, a second pattern positioned on a side where the intensity is high, and a step portion positioned between the first pattern and the second pattern so that a width of the first pattern is greater than a width of the second pattern.

8. The crystallization apparatus according to claim 7 , wherein the pupil of the image forming optical system has a light transmission area and a light semi-transmission area surrounding the light transmission area and, assuming that D 1 is a width of the first pattern of the two-stage inverse peak pattern, D 2 is a width of the second pattern of the same, θ 1 is a diameter of the light semi-transmission area represented by an angle and θ 2 is a diameter of the light transmission area represented by an angle, a size of a distribution of an outgoing radiation pupil function of the pupil of the image forming optical system satisfies the following expressions:

D 1 =k λ/sin θ1 ( k is a value from 0.5 to 2)

D 2 =kλ/sin θ 2 ( k is a value from 0.5 to 2).

9. The crystallization apparatus according to claim 1 , wherein a mask pattern of the mask has a phase shift mask having an intersection consisting of at least three or more phase shift lines and an integral value of a complex transmittance of a circular area with the intersection at the center being substantially zero.

10. The crystallization apparatus according to claim 9 , wherein each of the three or more phase shift lines has a phase difference being less than 180 degrees (π).

11. The crystallization apparatus according to claim 9 , wherein the number of phase shift lines is four, and each of the phase shift lines has a phase difference of substantially 90 degrees.

12. A crystallization method comprising:

generating an inverse peak pattern having a peak value that a light intensity is substantially zero at a phase shift portion of a phase shift mask by using this mask; and

irradiating a processed substrate with a light beam having the inverse peak pattern, thereby crystallizing at least a part of a substance of the substrate,

wherein an image of the light beam of the phase shift mask is formed on the processed substrate by using an image forming optical system provided between the phase shift mask and the processed substrate.

13. The crystallization method according to claim 12 , wherein an image of the light beam is formed with the processed substrate being held at a defocus position separated from a focal position of the image forming optical system by a predetermined distance, thereby achieving crystallization.

14. The crystallization method according to claim 12 , wherein the processed substrate is held at a focal position of the image forming optical system, and

the inverse peak pattern is made into a two-stage inverse peak pattern in such a manner that an outgoing radiation pupil function of the image forming optical system becomes a sum of two types of large and small distributions of an outer area and an inner area, and the processed substrate is irradiated with the light beam, thereby achieving crystallization.

15. The crystallization method according to claim 13 , wherein the processed substrate is held at a focal position of the image forming optical system, and

a width of the inverse peak pattern is adjusted by changing NA of the image forming optical system, and an image of the light beam is formed on the processed substrate, thereby achieving crystallization.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 6, 2011
From: ADVANCED LCD TECHNOLOGIES DEVELOPMENT CENTER CO., LTD.
To: SHARP KABUSHIKI KAISHA
Reel/Frame 026858/0705 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 15, 2003
From: TANIGUCHI, YUKIO; MATSUMURA, MASAKIYO; KIMURA, YOSHINOBU
To: ADVANCED LCD TECHNOLOGIES DEVELOPMENT CENTER CO., LTD.
Reel/Frame 014796/0949 →
Priority Claims (1)
JP 2002-120312 · Apr 23, 2002 · national
Continuity (2)
Continuation PCTJP030336600 · Mar 19, 2003
Related Publication 20040126674A1 · Jul 1, 2004