US5362667A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bonded wafer processing
Assignee: Intersil Corp
•
Filing: 1992-07-28
•
Granted: 1994-11-08
•
Expires: 2012-07-28
Abstract
Abstract Low temperature wafer bonding using a silicon-oxidizing bonding liquid permits introduction of radiation hardening dopants and electrically active dopants as constituents of the bonding liquid. Oxidizers such as nitric acid may be used in the bonding liquid. Dielectric layers on the device wafer and the handle wafer may be used when additional silicon is provided for the oxidative bonding. Integrated circuits fabricated from such bonded wafers may have buried layers and radiation hardening with device silicon too thick for implantation.
Inventors
- 👤 Jack H. Linn
- 👤 Robert K. Lowry
- 👤 George V. Rouse
- 👤 James F. Buller
- 👤 William H. Speece
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:32
CPC Classifications
H; H10; H10D; H10D86/00; H10D86/80; H10D86/85; H10P; H10P30/00; H10P30/20; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10W; H10W10/00; H10W10/01; H10W10/061; H10W10/10; H10W10/181; H10P90/1914; H10W10/011; H10W10/014; H10W10/041; H10W10/17; H10W10/40; Y; Y10; Y10S; Y10S148/00; Y10S148/012; Y10S438/00; Y10S438/914; Y10S438/92
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
56 words
A method of wafer bonding, comprising the steps of: (a) providing a device wafer and a handle wafer; (b) joining a surface of said device wafer to a surface of said handle wafer with a liquid quantity of oxidant therebetween; (c) heating said wafers in the range of about 800°-1000° C. wherein said wafers bond together.
Claim 2
Independent Claim
56 words
A method of wafer bonding, comprising the steps of: (a) providing a device wafer and a handle wafer; (b) joining a surface of said device wafer to a surface of said handle wafer with a liquid quantity of oxidant therebetween; (c) heating said wafers in the range of about 800°-1000° C. wherein said wafers bond together.
Claim 3
Dependent Claim
26 words
The method of claim 1, wherein: (a) said device wafer comprises silicon; and (b) said oxidant is characterized by reaction with silicon to yield silicon oxynitride.
Claim 4
Dependent Claim
33 words
The method of claim 2, wherein: (a) said quantity of oxidant is characterized by formation of a silicon oxynitride layer at said device wafer of thickness in the range of about 500-800 Å.
Claim 5
Dependent Claim
23 words
The method of claim 2, wherein: (a) said handle wafer is silicon with a dielectric layer at said surface of said handle wafer.
Claim 6
Dependent Claim
13 words
The method of claim 4, wherein: (a) said dielectric layer is silicon oxide.
Claim 7
Dependent Claim
20 words
The method of claim 4, wherein: (a) said dielectric layer is a silicon oxynitride sublayer on a silicon oxide sublayer.
Claim 8
Dependent Claim
13 words
The method of claim 4, wherein: (a) said dielectric layer includes aluminum oxide.
Claim 9
Dependent Claim
36 words
The method of claim 4, wherein: (a) said device wafer includes a second dielectric layer at said surface of said device wafer; and (b) said dielectric layer and said second dielectric layer together contain oxidizable silicon.
Claim 10
Dependent Claim
48 words
The method of claim 2, wherein: (a) said handle wafer is silicon with a dielectric layer at said surface of said handle wafer and with a silicon layer on said dielectric layer where said silicon layer contains less silicon than can be oxidized by said quantity of oxidant.
Claim 11
Dependent Claim
11 words
The method of claim 2, wherein: (a) said oxidant includes nitrate.
Claim 12
Dependent Claim
16 words
The method of claim 1, wherein: (a) said oxidant includes a compound of an electronegative dopant.
Claim 13
Dependent Claim
23 words
The method of claim 11, wherein: (a) said electronegative dopants are taken from the group consisting of fluorine, sulfur, phosphorus, and combinations thereof.
Claim 14
Independent Claim
71 words
A method of wafer bonding, comprising the steps of: (a) providing a device wafer and a handle wafer; (b) joining a surface of said device wafer to a surface of said handle wafer with a liquid oxidant therebetween, said oxidant including dopants which can be electrical active in said device wafer; and (c) heating said wafers wherein said wafers bond together and some of said dopants pass into said device wafer.
Claim 15
Independent Claim
71 words
A method of wafer bonding, comprising the steps of: (a) providing a device wafer and a handle wafer; (b) joining a surface of said device wafer to a surface of said handle wafer with a liquid oxidant therebetween, said oxidant including dopants which can be electrical active in said device wafer; and (c) heating said wafers wherein said wafers bond together and some of said dopants pass into said device wafer.
Claim 16
Dependent Claim
30 words
The method of claim 13, wherein: (a) said device wafer comprises silicon; and (b) said dopants are taken from the group consisting of boron, phosphorus, arsenic, antimony, and combinations thereof.
Claim 17
Dependent Claim
17 words
The method of claim 14, wherein: (a) said heating is in the range of about 800°-1000° C.
Claim 18
Dependent Claim
19 words
The method of claim 15, wherein: (a) said oxidant is characterized by reaction with silicon to yield silicon oxynitride.
Claim 19
Independent Claim
67 words
A method of wafer bonding, comprising the steps of: (a) providing a device wafer and a handle wafer; (b) joining a surface of said device wafer to a surface of said handle wafer with a quantity of liquid oxidant therebetween, wherein only one of said two surfaces comprises a dielectric layer; (c) heating said wafers in the range of about 800°-1000° C. wherein said wafers bond together.
Claim 20
Independent Claim
67 words
A method of wafer bonding, comprising the steps of: (a) providing a device wafer and a handle wafer; (b) joining a surface of said device wafer to a surface of said handle wafer with a quantity of liquid oxidant therebetween, wherein only one of said two surfaces comprises a dielectric layer; (c) heating said wafers in the range of about 800°-1000° C. wherein said wafers bond together.
Claim 21
Dependent Claim
26 words
The method of claim 17, wherein: (a) said device wafer comprises silicon; and (b) said oxidant is characterized by reaction with silicon to yield silicon oxynitride.
Claim 22
Dependent Claim
33 words
The method of claim 18, wherein: (a) said quantity of oxidant is characterized by formation of a silicon oxynitride layer at said device wafer of thickness in the range of about 500-800 Å.
Claim 23
Dependent Claim
23 words
The method of claim 18, wherein: (a) said handle wafer is silicon with a dielectric layer at said surface of said handle wafer.
Claim 24
Dependent Claim
13 words
The method of claim 20, wherein: (a) said dielectric layer is silicon oxide.
Claim 25
Dependent Claim
20 words
The method of claim 20, wherein: (a) said dielectric layer is a silicon oxynitride sublayer on a silicon oxide sublayer.
Claim 26
Dependent Claim
13 words
The method of claim 20, wherein: (a) said dielectric layer includes aluminum oxide.
Claim 27
Dependent Claim
11 words
The method of claim 18, wherein: (a) said oxidant includes nitrate.
Claim 28
Dependent Claim
16 words
The method of claim 17, wherein: (a) said oxidant includes a compound of an electronegative dopant.
Claim 29
Dependent Claim
23 words
The method of claim 25, wherein: (a) said electronegative dopants are taken from the group consisting of fluorine, sulfur, phosphorus, and combinations thereof.
References Cited (Backward Citations)
US4878957A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-11-07 | 1998-05-09 | 1998-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-07 | 2002-05-09 | 2002-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-07 | 2006-05-09 | 2006-11-08 | $7700.00 | Window Closed / Lapsed |