US4712013A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming a fine pattern with a charged particle beam
Assignee: Toshiba Corp
•
Filing: 1987-05-04
•
Granted: 1987-12-08
•
Expires: 2007-05-04
Abstract
Abstract A method of forming a fine pattern with a charged beam, comprises steps of irradiating, with a charged beam, a predetermined region of a sample to form an exposure pattern on the sample, and irradiating, with at least one of a charged beam or an electromagnetic wave, and at a dose smaller than the dose for forming the main pattern, the entire surface of the specific pattern and nonpattern regions around the specific pattern region to perform an auxiliary exposure. The step of performing the auxiliary exposure is performed at a high voltage of, for example, more than 30 KeV so as not to change the molecular distribution along the direction of thickness of an irradiated portion of the sample.
Inventors
- 👤 Eiji Nishimura
- 👤 Tadahiro Takigawa
- 👤 Yoshihide Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:28
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/30; H01J37/317; H01J37/3174; B; B82; B82Y; B82Y10/00; B82Y40/00; G; G03; G03F; G03F7/00; G03F7/20; G03F7/2022; H01J2237/00; H01J2237/30; H01J2237/304; H01J2237/30472; H01J2237/30483; H01J2237/30488; H01J2237/317; H01J2237/3175; H01J2237/31769; H01J2237/31771; H01J2237/31777; H01J2237/31779
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
122 words
A method of forming a fine pattern with a charged beam, comprising the steps of: performing a first irradiation of a predetermined region of a sample with a charged beam to form an exposed pattern on the sample; and performing a second irradiation of a region around the pattern with either of a charged beam or an electromagnetic wave, and at a dose smaller than the dose for forming the exposure pattern, to perform an auxiliary exposure, the auxiliary exposure being such that a molecular amount distribution remains substantially unchanged along the direction of thickness of said region around the pattern of the sample wherein the step of performing the auxiliary exposure occurs at a voltage of not less than 30 keV.
Claim 2
Independent Claim
122 words
A method of forming a fine pattern with a charged beam, comprising the steps of: performing a first irradiation of a predetermined region of a sample with a charged beam to form an exposed pattern on the sample; and performing a second irradiation of a region around the pattern with either of a charged beam or an electromagnetic wave, and at a dose smaller than the dose for forming the exposure pattern, to perform an auxiliary exposure, the auxiliary exposure being such that a molecular amount distribution remains substantially unchanged along the direction of thickness of said region around the pattern of the sample wherein the step of performing the auxiliary exposure occurs at a voltage of not less than 30 keV.
Claim 3
Dependent Claim
32 words
A method according to claim 1, wherein the step of performing the auxiliary exposure is performed at a dose which is less than 50% of the dose for forming the exposure pattern.
Claim 4
Dependent Claim
43 words
A method according to claim 1, wherein the step of forming the exposure pattern comprises the step of irradiating a photoelectric mask with light which emits an electron beam of a predetermined pattern, said electron beam irradiating the predetermined region of the sample.
Claim 5
Dependent Claim
17 words
A method according to claim 1, wherein the exposure pattern is formed by delineating the predetermined region.
Claim 6
Dependent Claim
40 words
A method according to claim 1, wherein the step of performing the auxiliary exposure is performed by a beam source which is one of an electron beam, an ion beam, an ultraviolet ray, a far ultraviolet ray an an X-ray.
Claim 7
Dependent Claim
24 words
A method according to claim 1, wherein the step of performing the auxiliary exposure occurs at a voltage of not less than 40 keV.
Claim 8
Dependent Claim
18 words
A method according to claim 1, wherein the pattern is formed on a radiation-sensitive film of the sample.
Claim 9
Dependent Claim
34 words
A method according to claim 1, further comprising the subsequent step of performing a secondary auxiliary exposure which exposes the entire surface of said sample with either a charged beam or an electromagnetic wave.
Claim 10
Dependent Claim
31 words
A method according to claim 1, further comprising the step of selectively performing a third irradiation on a specific correction pattern region with either a charged beam or an electromagnetic wave.
Claim 11
Independent Claim
126 words
A method of forming a fine pattern with a charged beam, comprising the steps of: performing a first irradiation of a predetermined region of a sample with a charged beam to form an exposed pattern on the sample; and performing a second irradiation of the predetermined region and a region around said predetermined region with either a charged beam or an electromagnetic wave, and at a dose smaller than the dose for forming the exposure pattern, to perform an auxiliary exposure, the auxiliary exposure being such that a molecular amount distribution remains substantially unchanged along the direction of thickness of said region around the pattern of the sample wherein the step of performing the auxiliary exposure occurs at a voltage of not less than 30 keV.
Claim 12
Independent Claim
126 words
A method of forming a fine pattern with a charged beam, comprising the steps of: performing a first irradiation of a predetermined region of a sample with a charged beam to form an exposed pattern on the sample; and performing a second irradiation of the predetermined region and a region around said predetermined region with either a charged beam or an electromagnetic wave, and at a dose smaller than the dose for forming the exposure pattern, to perform an auxiliary exposure, the auxiliary exposure being such that a molecular amount distribution remains substantially unchanged along the direction of thickness of said region around the pattern of the sample wherein the step of performing the auxiliary exposure occurs at a voltage of not less than 30 keV.
Claim 13
Dependent Claim
32 words
A method according to claim 10, wherein the step of performing the auxiliary exposure is performed at a dose which is less than 50% of the dose for forming the exposure pattern.
Claim 14
Dependent Claim
43 words
A method according to claim 10, wherein the step of forming the exposure pattern comprises the step of irradiating a photoelectric mask with light which emits an electron beam of a predetermined pattern, said electron beam irradiating the predetermined region of the sample.
Claim 15
Dependent Claim
17 words
A method according to claim 10, wherein the exosure pattern is formed by delineating the predetermined region.
Claim 16
Dependent Claim
40 words
A method according to claim 10, wherein the step of performing the auxiliary exposure is performed by a beam source which is one of an electron beam, an ion beam, an ultraviolet ray, a far ultraviolet ray and an X-ray.
Claim 17
Dependent Claim
24 words
A method according to claim 10, wherein the step of performing the auxiliary exposure occurs at a voltage of not less than 40 keV.
Claim 18
Dependent Claim
18 words
A method according to claim 10, wherein the pattern is formed on a radiation-sensitive film of the sample.
Claim 19
Dependent Claim
46 words
A method according to claim 10, comprising the further step of performing a third irradiation on entire sample with either a charged beam or an electromagnetic wave after the step of performing a second irradiation of predetermined region of said sample to form an exposed pattern.
References Cited (Backward Citations)
JPS52117077A
Cited
US4099062A
Cited
US4298803A
Cited
US4392058A
Cited
JPS5646258A
Cited
US4264711A
Cited
US4426584A
Cited
US4504558A
Cited
JPS59921A
Cited
US4463265A
Cited
EP0097903A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-12-07 | 1991-06-08 | 1991-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-12-07 | 1995-06-08 | 1995-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-12-07 | 1999-06-08 | 1999-12-08 | $7700.00 | Window Closed / Lapsed |