US5369057A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making and sealing a semiconductor device having an air path therethrough
Assignee: Delphi Technologies Inc
•
Filing: 1993-12-21
•
Granted: 1994-11-29
•
Expires: 2013-12-21
Abstract
Abstract This invention generally relates to the provision of a vent path during the bonding of silicon wafers and the subsequent encapsulation of the individual devices. A double-sided polished silicon wafer is used for the device wafer. The device wafer includes circuitry, thin membranes and metal interconnections. When bonding a bottom wafer to the device wafer, a vented path exists between the wafers. The venting path includes serpentine shape channel formed by interdigitated fingers and cavities. The cavity and the interdigitated patterns can be etched either together or separately into either wafer. A top wafer has a cavity formed therein. When the top device and bottom wafers are bonded together, the venting path is sealed by dipping the device in a sealing liquid. The serpentine path prevents the sealing liquid from reaching the cavity.
Inventors
- 👤 Han-Sheng Lee
- 👤 Steven E. Staller
- 👤 James H. Logsdon
- 👤 Dan W. Chilcott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:24
CPC Classifications
G; G01; G01P; G01P1/00; G01P1/02; G01P1/023; G01P15/00; G01P15/02; G01P15/08; G01P15/0802; H; H10; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W95/00; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49082; Y10T29/49103
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
112 words
A method of making an accelerometer comprising: providing a first wafer having a support shoulder and a proof mass suspended by a thin membrane bridge between the support shoulder and proof mass, and an associated circuitry for detecting deflection of the proof mass upon extreme acceleration, providing a second wafer having a cavity formed therein, for accommodating the deflection of the proof mass of the first wafer, at least one serpentine venting path formed in the at least one of said wafers; bonding the first and second wafers together; and exposing the bonded wafers to a sealing composition so that the sealing composition enters the serpentine venting path to seal the device.
Claim 2
Independent Claim
112 words
A method of making an accelerometer comprising: providing a first wafer having a support shoulder and a proof mass suspended by a thin membrane bridge between the support shoulder and proof mass, and an associated circuitry for detecting deflection of the proof mass upon extreme acceleration, providing a second wafer having a cavity formed therein, for accommodating the deflection of the proof mass of the first wafer, at least one serpentine venting path formed in the at least one of said wafers; bonding the first and second wafers together; and exposing the bonded wafers to a sealing composition so that the sealing composition enters the serpentine venting path to seal the device.
Claim 3
Dependent Claim
18 words
A method as set forth in claim 1 wherein said serpentine venting path is formed by interdigitated finger.
Claim 4
Dependent Claim
24 words
A method as set forth in claim 2 wherein cavity and interdigitated finger are formed by selectively etching at least one of said wafers.
Claim 5
Dependent Claim
14 words
A method as set forth in claim 1 wherein the composition comprises an epoxy.
Claim 6
Dependent Claim
15 words
A method as set forth in claim 1 wherein the composition comprises a dielectric material.
Claim 7
Independent Claim
118 words
A method of making an accelerometer comprising: forming a wafer comprising silicon and including a proof mass suspended by at least one thin bridge extending between said proof mass and a support member defined in said wafer, and a thin membrane extending between said proof mass, bridge and support member; forming a serpentine-shaped venting path in said accelerometer; exposing said wafer to a plasma to remove said thin membrane and wherein said serpentine-shaped venting path is constructed and arranged to vent gases, associated with removing said thin membrane, out of the accelerometer; and exposing said accelerometer to a sealing composition so that the sealing composition enters the serpentine venting path but does not extend all the way therethrough.
Claim 8
Independent Claim
118 words
A method of making an accelerometer comprising: forming a wafer comprising silicon and including a proof mass suspended by at least one thin bridge extending between said proof mass and a support member defined in said wafer, and a thin membrane extending between said proof mass, bridge and support member; forming a serpentine-shaped venting path in said accelerometer; exposing said wafer to a plasma to remove said thin membrane and wherein said serpentine-shaped venting path is constructed and arranged to vent gases, associated with removing said thin membrane, out of the accelerometer; and exposing said accelerometer to a sealing composition so that the sealing composition enters the serpentine venting path but does not extend all the way therethrough.
References Cited (Backward Citations)
US4706374A
Cited
JPH01195368A
Cited
JPH01245163A
Cited
US4930043A
Cited
US5006487A
Cited
US5068203A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-11-28 | 1998-05-30 | 1998-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-28 | 2002-05-30 | 2002-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-28 | 2006-05-30 | 2006-11-29 | $7700.00 | Window Closed / Lapsed |