Patent EP0121412A2 successfully refreshed from Google Patents.
EP0121412A2
Expired / Lapsed
EP
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Method of forming by projection an integrated circuit pattern on a semiconductor wafer
Assignee: Toshiba Corp
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Filing: 1984-03-28
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Granted: —
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Expires: 2004-03-28
Abstract
Abstract Disclosed is a method of forming by projection an integrated circuit pattern on a first semiconductor wafer. A plurality of reference marks are projected onto a second semiconductor wafer (44) by the irradiation of radiant rays from a projector apparatus used to form the integrated circuit pattern onto the first semiconductor wafer. The positions of the reference marks projected onto the second semiconductor wafer (44) are measured, thereby measuring the projection distortion peculiar to the projector apparatus. As the next step, a projection mask (68) used to form the integrated circuit pattern is produced with the use of the measured projection distortions which has a distortion opposite that of the projector so as to offset its projection distortion. The mark is mounted in the projector apparatus, and the radiant rays are irradiated onto the mask thus projecting the integrated circuit pattern onto the first semiconductor wafer.
Inventors
- 👤 Mineo Gotou
- 👤 Shunichi Sano
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 08:17
CPC Classifications
B; B82; B82Y; B82Y10/00; G; G03; G03F; G03F7/00; G03F7/70; G03F7/70425; G03F7/70433; B82Y40/00; G03F7/7045; G03F7/70483; G03F7/70591; G03F7/706; H; H01; H01J; H01J37/00; H01J37/30; H01J37/304; H01J37/3045; H01J37/317; H01J37/3174; H01J2237/00; H01J2237/30; H01J2237/304; H01J2237/30433
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
178 words
A method of forming by projection an integrated circuit pattern on a first semiconductor wafer by irradiating radiant rays onto a mask used to form the integrated circuit pattern characterized in that said method comprises the steps of: irradiating radiant rays onto a mask provided with plurality of reference marks by the use of a projector apparatus which is used to form the integrated circuit pattern on said first semiconductor wafer, thereby projecting said plurality of reference marks onto a second semiconductor wafer; measuring the projection distortions peculiar to said projector apparatus by measuring the positions of said reference marks projected onto said second semiconductor wafer; producing a projection mask for use in the formation of the integrated circuit pattern by using the measured projection distortion, said projection mask being formed by being given an opposite distortion so as to offset the projection distortion peculiar to said projector apparatus; and mounting the projection mask in said projector apparatus and irradiating radiant rays onto said projection mask, thereby forming the integrated circuit pattern onto the first semiconductor wafer (26).
Claim 2
Independent Claim
178 words
A method of forming by projection an integrated circuit pattern on a first semiconductor wafer by irradiating radiant rays onto a mask used to form the integrated circuit pattern characterized in that said method comprises the steps of: irradiating radiant rays onto a mask provided with plurality of reference marks by the use of a projector apparatus which is used to form the integrated circuit pattern on said first semiconductor wafer, thereby projecting said plurality of reference marks onto a second semiconductor wafer; measuring the projection distortions peculiar to said projector apparatus by measuring the positions of said reference marks projected onto said second semiconductor wafer; producing a projection mask for use in the formation of the integrated circuit pattern by using the measured projection distortion, said projection mask being formed by being given an opposite distortion so as to offset the projection distortion peculiar to said projector apparatus; and mounting the projection mask in said projector apparatus and irradiating radiant rays onto said projection mask, thereby forming the integrated circuit pattern onto the first semiconductor wafer (26).
Claim 3
Dependent Claim
96 words
The method according to claim 1, characterized in that said projection distortion measuring step comprises the substeps of: mounting in said projector apparatus the projection distortion measuring mask formed with a plurality of marks in the form of a matrix; projecting said marks of said projection distortion measuring mask onto the second semiconductor wafer; and measuring a difference between the position of each mark formed on the second semiconductor wafer and the position at which said mark should be formed, thereby measuring the projection distortion (Axi, Ayi) made on each position of the second semiconductor wafer.
Claim 4
Dependent Claim
50 words
The method according to claim 2, characterized in that said projection mask producing step comprises the substep wherein, when said projector apparatus is assumed to have a projection magnification of k, an opposite distortion (- Δxi, - Δyi) is imparted beforehand to the integrated circuit pattern on the projection mask.
Claim 5
Dependent Claim
106 words
The method according to claim 2, characterized in that said projection mask producing step is carried out by using an electron beam exposure apparatus (40)including: a memory (66) for holding said opposite distortion values (AXi, AYi) produced in accordance with said projection distortion (Axi, Ayi); an adder (82) for adding said opposite distortion values (AXi, AYi) held in said memory to the exposure position data corresponding to a design pattern constituting the integrated circuit pattern, thereby obtaining a corrected exposure position data; and a deflection signal generating circuit (86) so arranged as to change the amount of deflection in accordance with said corrected exposure position data.
Claim 6
Dependent Claim
40 words
The method according to claim 4, characterized in that said opposite distortion values (AXi, AYi) are expressed such that AX i = - Δxi and AY i = - Δyi where k represents the projection magnification of said projector apparatus.
Claim 7
Dependent Claim
96 words
The method according to claim 4, characterized in that said substep of measuring said difference between the position of each mark formed on the second semiconductor wafer and the position at which said mark should be formed is executed with the use of said electron beam exposure apparatus by: irradiating electron beams onto the second semiconductor wafer (44) having said plurality of reference marks projected thereon; detecting the electron reflected from the second semiconductor wafer, thereby detecting the mark position thereon; and measuring the difference between the mark position and the mark position to be formed.
Claim 8
Dependent Claim
20 words
The method according to claim 1, characterized in that said projector apparatus is an optical projector apparatus for light exposure.
Claim 9
Dependent Claim
41 words
The method according to claim 1, characterized in that said projector apparatus is an electron beam projector apparatus so arranged as to irradiate light onto a photoelectric conversion mask to obtain an electron beam pattern and to expose the electron beams.
Claim 10
Dependent Claim
21 words
The method according to claim 1, characterized in that said projector apparatus is an X-ray projector apparatus for exposing X rays.
References Cited (Backward Citations)
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