EP0289249A2
Expired / Lapsed
EP
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Device fabrication by X-ray lithography utilizing stable boron nitride mask
Assignee: AT&T Inc
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Filing: 1988-04-25
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Granted: —
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Expires: 2008-04-25
Abstract
Abstract A hydrogen-free boron-containing membrane (28) is a state of tension exhibits advantageous properties for use in a mask for X-ray lithography.
Inventors
- 👤 Roland Albert Levy
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 06:33
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/22; Y; Y10; Y10S; Y10S430/00; Y10S430/167; Y10S430/168
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
43 words
A process for fabricating devices by X-ray lithography wherein a mask comprising an X-ray-opaque device pattern (32) is aligned with respect to a device workpiece (16) and is irradiated with X-rays, CHARACTERIZED IN THAT that the mask comprises a hydrogen-free boron-containing membrane (28).
Claim 2
Dependent Claim
43 words
A process for fabricating devices by X-ray lithography wherein a mask comprising an X-ray-opaque device pattern (32) is aligned with respect to a device workpiece (16) and is irradiated with X-rays, CHARACTERIZED IN THAT that the mask comprises a hydrogen-free boron-containing membrane (28).
Claim 3
Dependent Claim
27 words
A process as in claim 1 wherein the mask comprises a hydrogen-free BN membrane (28) and means (26) for maintaining the membrane in a state of tension.
Claim 4
Dependent Claim
23 words
A process as in claim 2 wherein the maintaining means comprises a layer (26) of hydrogen-free B₃N located on the BN membrane (28).
Claim 5
Dependent Claim
21 words
A process as in claim 3 wherein a barrier layer to diffusion of boron is situated on the layer of B₃N.
Claim 6
Dependent Claim
33 words
A process as in claim 4 wherein ports are formed in the diffusion barrier layer and in the layer of B₃N, for viewing corresponding alignment marks formed on the mask and the workpiece.
Claim 7
Dependent Claim
23 words
A process as in claim 2 wherein the maintaining means comprises a stress-inducing constituent material added to the material of the BN membrane.
Claim 8
Dependent Claim
12 words
A process as in claim 6 wherein the constituent material comprises silicon.
Claim 9
Dependent Claim
30 words
A process as in claim 2 wherein the maintaining means comprises a ring member in contact with peripheral portions of the BN membrane for imparting tensile forces to the membrane.
Claim 10
Dependent Claim
15 words
A process as in claim 1 wherein the mask further comprises a hydrogen-free B₃N membrane.
Claim 11
Dependent Claim
20 words
A process as in claim 9 wherein a barrier layer to duffusion of boron is situated on the B₃N membrane.
Claim 12
Dependent Claim
34 words
A process as in claim 10 wherein there are ports in the diffusion barrier layer and in the B₃N membrane for viewing corresponding alignment marks are formed on the mask and on the workpiece.
Claim 13
Dependent Claim
14 words
A process as in claim 1 wherein the membrane comprises a hydrogen-free boron membrane.
Claim 14
Dependent Claim
44 words
A mask structure for use in fabricating devices by X-ray lithography, the structure comprising an X-ray transparent membrane (28), and an X-ray-opaque device pattern (32) formed on the membrane, CHARACTERIZED IN THAT the membrane (28) comprises a hydrogen-free layer in a state of tension.
Claim 15
Dependent Claim
44 words
A mask structure for use in fabricating devices by X-ray lithography, the structure comprising an X-ray transparent membrane (28), and an X-ray-opaque device pattern (32) formed on the membrane, CHARACTERIZED IN THAT the membrane (28) comprises a hydrogen-free layer in a state of tension.
Claim 16
Dependent Claim
21 words
A structure as in claim 13 wherein the membrane (28) comprises a hydrogen-free boron nitride layer in a state of tension.
Claim 17
Dependent Claim
71 words
In a system designed to define device features by X-ray lithography: an X-ray-transparent mask having X-ray-opaque device features (32) formed thereon, the mask comprising a boron-containing membrane (28), a device workpiece (16) aligned with respect to the mask, and means irradiating the mask with X-rays to cause the device features to be defined on the workpiece, CHARACTERIZED IN THAT the membrane (28) is hydrogen-free and is in a state of tension.
Claim 18
Dependent Claim
71 words
In a system designed to define device features by X-ray lithography: an X-ray-transparent mask having X-ray-opaque device features (32) formed thereon, the mask comprising a boron-containing membrane (28), a device workpiece (16) aligned with respect to the mask, and means irradiating the mask with X-rays to cause the device features to be defined on the workpiece, CHARACTERIZED IN THAT the membrane (28) is hydrogen-free and is in a state of tension.
Claim 19
Dependent Claim
20 words
A combination as in claim 15 wherein the membrane comprises a hydrogen-free boron nitride member in a state of tension.
Claim 20
Independent Claim
82 words
A device manufacturing method comprising the steps of forming an X-ray-opaque device pattern on a portion of a boron-and-hydrogen-containing membrane in a state of tension, the portion being adapted to be irradiated with X-rays, and irradiating the portion with X-rays to project the pattern onto a device workpiece that is aligned with respect to the membrane CHARACTERIZED BY the step of annealing only the portion of said membrane to remove hydrogen therefrom, prior to the step of irradiating the portion with X-rays.
Claim 21
Independent Claim
82 words
A device manufacturing method comprising the steps of forming an X-ray-opaque device pattern on a portion of a boron-and-hydrogen-containing membrane in a state of tension, the portion being adapted to be irradiated with X-rays, and irradiating the portion with X-rays to project the pattern onto a device workpiece that is aligned with respect to the membrane CHARACTERIZED BY the step of annealing only the portion of said membrane to remove hydrogen therefrom, prior to the step of irradiating the portion with X-rays.
Claim 22
Dependent Claim
27 words
A method as in claim 17 wherein the workpiece is aligned with the membrane by utilizing an optically transparent property of an unannealed portion of the membrane.
References Cited (Backward Citations)
No citation records indexed.
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