US5709773A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicon microstructures and process for their fabrication
Assignee: Agilent Technologies Inc
•
Filing: 1996-11-15
•
Granted: 1998-01-20
•
Expires: 2016-11-15
Abstract
Abstract A flexible and efficient bulk micromachining method for fabricating a novel microstructure that is bounded by substantially planar surfaces meeting only at substantially right angle corner features. The novel microstructure of the present invention is useful as a spacer in assembly processes where high accuracy is required, such as precise positioning of optical fibers or conductors. In the preferred embodiment, the microstructure of the present invention includes a shelf feature disposed along a height dimension of the microstructure, which is required for some applications. The bulk micromachining method of the present invention includes providing a first substrate having a top planar surface and an opposing planar surface. The opposing surface of the substrate is anisotropically etched to provide a first thinned region. The top surface of the first substrate is anisotropically etched so that a first recessed feature having a vertical side is made integral with the first thinned region. Similarly, a second substrate having a top planar surface and an opposing planar surface is provided. The opposing surface of the second substrate is anisotropically etched to provide a second thinned region. The top surface of the second substrate is anisotropically etched so that a second recessed feature having a vertical side wall is made integral with the second thinned region. The top surface of the first substrate is aligned and coupled with the top surface of the second substrate to produce the desired microstructure. The substrates are cut or sawn to free the microstructure.
Inventors
- 👤 Leslie A. Field
- 👤 Phillip W. Barth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:03
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/36; G02B6/3628; G02B6/3684; G02B6/3692; G02B6/3632; G02B6/3636; G02B6/38; G02B6/3807; G02B6/3833; G02B6/3834; G02B6/3838; G02B6/42; G02B6/4201; G02B6/4219; G02B6/4228; G02B6/423; G02B6/4231; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
152 words
A bulk micromachining method comprising the steps of: providing a first substrate having first and second opposing surfaces; etching the second surface of the substrate to provide a first thinned region; and anisotropically etching a first recessed feature having a vertical side wall into the first surface of the first substrate so that the first recessed feature is integral with the first thinned region; providing a second substrate including third and fourth opposing surfaces; etching the fourth surface of the second substrate to provide a second thinned region; anisotroically etching a second recessed feature having a vertical side wall into the third surface of the second substrate so that the second recessed feature is integral with the second thinned region; coupling the first surface of the first substrate to the third surface of the second substrate; and severing a portion of the coupled substrates so as to provide a free standing microstructure.
Claim 2
Dependent Claim
152 words
A bulk micromachining method comprising the steps of: providing a first substrate having first and second opposing surfaces; etching the second surface of the substrate to provide a first thinned region; and anisotropically etching a first recessed feature having a vertical side wall into the first surface of the first substrate so that the first recessed feature is integral with the first thinned region; providing a second substrate including third and fourth opposing surfaces; etching the fourth surface of the second substrate to provide a second thinned region; anisotroically etching a second recessed feature having a vertical side wall into the third surface of the second substrate so that the second recessed feature is integral with the second thinned region; coupling the first surface of the first substrate to the third surface of the second substrate; and severing a portion of the coupled substrates so as to provide a free standing microstructure.
Claim 3
Dependent Claim
44 words
A method as in claim 1 wherein: the first substrate has a crystalline structure that includes a set of {100} crystal lattice planes; and the vertical side wall of the first recessed feature is a member of the set of {100} crystal lattice planes.
Claim 4
Dependent Claim
112 words
A method as in claim 1 wherein: the first substrate has a crystalline structure that includes a set of <100> crystal lattice directions, the first surface of the first substrate being orthogonal to a member of the set of <100> crystal lattice directions; and the anisotropic etching step includes: masking the first surface of the first substrate using a first mask layer having a first mask edge, the first mask edge having a longitudinal dimension; orienting the longitudinal dimension of the first mask edge along another member of the set of <100> crystal lattice directions; and anisotropically etching the first substrate so that the first recessed feature undercuts the first mask edge.
Claim 5
Dependent Claim
36 words
A method as in claim 3 wherein the step of severing the portion of the coupled substrates includes laser scribing each of the substrates along yet another member of the set of <100> crystal lattice directions.
Claim 6
Dependent Claim
35 words
A method as in claim 3 wherein the step of severing the portion of the coupled substrates includes sawing each of the substrates along yet another member of the set of <100> crystal lattice directions.
Claim 7
Dependent Claim
27 words
A method as in claim 1 wherein the coupling step includes bonding the first surface of the first substrate to the third surface of the second substrate.
Claim 8
Dependent Claim
28 words
A method as in claim 1 wherein the coupling step includes fusion bonding the first surface of the first substrate to the third surface of the second substrate.
Claim 9
Dependent Claim
31 words
A method as in claim 1 wherein the coupling step includes aligning the substrates so that the first recessed feature is contacts the second substrate adjacent to the second recessed feature.
Claim 10
Dependent Claim
27 words
A method as in claim 1 wherein the coupling step includes aligning the substrates so that the first recessed feature is adjacent to the second recessed feature.
Claim 11
Dependent Claim
74 words
A method as in claim 9 wherein the coupling step further includes: etching a respective set of alignment grooves into the respective top surface of each substrate; placing alignment fibers into the grooves of the second substrate so that a portion of each fiber is disposed in a respective one of the grooves; and aligning the first substrate with the second substrate so that each fiber engages a respective groove of the first substrate.
Claim 12
Dependent Claim
38 words
A method as in claim 9 wherein the coupled substrates are aligned so that the freestanding microstructure a shelf feature formed by the vertical side wall of the first feature and the third surface of the second substrate.
Claim 13
Dependent Claim
32 words
A method as in claim 11 wherein the substrates are coupled so that the vertical side wall of the first recessed feature is orthogonal to the third surface of the second substrate.
Claim 14
Dependent Claim
92 words
A bulk micromachining method comprising the steps of: providing a first and second substrate each having a respective top surface; anisotropically etching a first recessed feature into the top surface of the first substrate; anisotropically etching a second recessed feature into the top surface of the second substrate; aligning the top surface of the first substrate with the top surface of the second substrate so that the first feature is adjacent to the second feature; and coupling the top surface of the first substrate with the top surface of the second substrate.
Claim 15
Dependent Claim
92 words
A bulk micromachining method comprising the steps of: providing a first and second substrate each having a respective top surface; anisotropically etching a first recessed feature into the top surface of the first substrate; anisotropically etching a second recessed feature into the top surface of the second substrate; aligning the top surface of the first substrate with the top surface of the second substrate so that the first feature is adjacent to the second feature; and coupling the top surface of the first substrate with the top surface of the second substrate.
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) | 2001-01-19 | 2001-07-21 | 2002-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-01-19 | 2005-07-21 | 2006-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-01-19 | 2009-07-21 | 2010-01-20 | $7700.00 | Window Closed / Lapsed |