Patent US4668336A successfully refreshed from Google Patents.
US4668336A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making a mask used in x-ray photolithography
Assignee: Micronix Corp
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Filing: 1986-05-23
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Granted: 1987-05-26
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Expires: 2006-05-23
Abstract
Abstract A method of manufacturing a mask for use in x-ray photolithography includes the steps of coating a set of wafers (20) with boron nitride (22). The tension in the boron nitride is measured by using a capacitive probe (26) to measure bowing in a set of test wafers. The remaining wafers are attached to a pyrex ring (28), and the boron nitride is removed from one side of the wafers. A circular hole is then etched in the wafer, and a layer of tantalum (32) and gold (34) are formed on the remaining boron nitride membrane. The gold (34) is patterned via a sputter etching process. Power is reduced at the end of the sputter etching process slowly to reduce mechanical stress in the mask. The tantalum (32) is then etched via a reactive ion etching process. In this way, an x-ray transparent boron nitride membrane is used to support x-ray opaque gold.
Inventors
- 👤 Alexander R. Shimkunas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:28
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/22
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
84 words
A method for manufacturing a mask comprising the steps of: providing a membrane, said membrane being covered by a layer of a first substance, said layer of said first substance being covered by patterned layer of a second substance; transferring the pattern in said patterned layer of said second substance to said layer of said first substance via a sputter etching process, said sputter etching process being performed in an etching apparatus; and reducing power to said etching apparatus over a period of time.
Claim 2
Independent Claim
84 words
A method for manufacturing a mask comprising the steps of: providing a membrane, said membrane being covered by a layer of a first substance, said layer of said first substance being covered by patterned layer of a second substance; transferring the pattern in said patterned layer of said second substance to said layer of said first substance via a sputter etching process, said sputter etching process being performed in an etching apparatus; and reducing power to said etching apparatus over a period of time.
Claim 3
Dependent Claim
17 words
The method of claim 1 wherein said first substance is tantalum and said second substance is gold.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein said membrane comprises boron nitride.
Claim 5
Dependent Claim
18 words
The method of claim 1 wherein said power is reduced over a period of at least 14 minutes.
Claim 6
Dependent Claim
23 words
The method of claim 1 wherein said power is reduced from 300 watts to 0 watts in 25 watt increments every two minutes.
Claim 7
Independent Claim
71 words
A method for sputter etching comprising the steps of: providing a first layer of a first material having a top surface covered by a second layer of a second material; forming a paterned masking layer on said second layer of said second material; transferring the pattern in said masking layer to said second layeer by sputter etching; and reducing the power used in said sputter etching over a period of time.
Claim 8
Independent Claim
71 words
A method for sputter etching comprising the steps of: providing a first layer of a first material having a top surface covered by a second layer of a second material; forming a paterned masking layer on said second layer of said second material; transferring the pattern in said masking layer to said second layeer by sputter etching; and reducing the power used in said sputter etching over a period of time.
Claim 9
Independent Claim
34 words
A method for sputter etching comprising the steps of: providing a layer of material; sputter etching said layer of material; and reducing the power used in said sputter etching over a period of time.
Claim 10
Independent Claim
34 words
A method for sputter etching comprising the steps of: providing a layer of material; sputter etching said layer of material; and reducing the power used in said sputter etching over a period of time.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-05-25 | 1990-11-24 | 1991-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-25 | 1994-11-24 | 1995-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-25 | 1998-11-24 | 1999-05-26 | $7700.00 | Window Closed / Lapsed |