Patent EP0561532A2 successfully refreshed from Google Patents.
EP0561532A2
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EP
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Method of manufacturing an integrated circuit including planarizing a wafer
Assignee: AT&T Inc
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Filing: 1993-03-04
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Granted: —
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Expires: 2013-03-04
Abstract
Abstract A process for planarizing a bonded wafer (5). The wafer has a layer of exposed oxide (4) thereon which acts as a reference for the grinding and polishing of the wafer. The resulting ground and polished wafer has a thinned, substantially planar, working layer (1) for subsequent fabrication of transistors, etc. <IMAGE>
Inventors
- 👤 William Graham Easter
- 👤 Richard Handly Shanaman, Iii
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 10:36
CPC Classifications
H; H10; H10P; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/1914; H10P52/00; H10P52/40; H10P52/402; H10W; H10W10/00; H10W10/10; H10W10/181; Y; Y10; Y10S; Y10S148/00; Y10S148/012; Y10S438/00; Y10S438/977
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
96 words
A method of making an integrated circuit, CHARACTERIZED BY THE STEPS OF: forming an oxide layer (3,4) on each major surface of a handle wafer (2): bonding an working wafer (1) to the handle wafer to form a bonded wafer having a working layer, a handle layer, and an exposed oxide layer, the working layer being insulated from the handle layer, and polishing both major surfaces of the bonded wafer to thin the working layer to a predetermined thickness using the exposed oxide layer as a planar reference so as to form a substantially planar wafer.
Claim 2
Dependent Claim
31 words
The method of making an integrated circuit as recited in claim 1, further characterized by the step of: grinding the bonded wafer to a predetermined thickness prior to the polishing thereof.
Claim 3
Dependent Claim
37 words
The method of making an integrated circuit as recited in claim 2, wherein the polishing step uses an etchant that selectively removes the material of the working layer relative to the oxide layer on the handle layer.
Claim 4
Dependent Claim
26 words
The method of making an integrated circuit as recited in claim 3, further characterized by the step of: removing the exposed oxide layer on handle layer.
Claim 5
Dependent Claim
24 words
The method of making an integrated circuit as recited in claim 4, wherein the working layer and the handle layer are comprised of silicon.
Claim 6
Independent Claim
67 words
A method of making an integrated circuit, CHARACTERIZED BY THE STEPS OF: forming an oxide layer (4) on at least one major surface of a semiconductor wafer (5): and polishing the wafer, on both major surfaces thereof, to a predetermined thickness using the oxide layer as a planar reference, so as to form a substantially planar wafer: wherein the layer of oxide remains after the polishing step.
Claim 7
Dependent Claim
30 words
The method of making an integrated circuit as recited in claim 6, further characterized by the step of: grinding the wafer to a predetermined thickness prior to the polishing step.
Claim 8
Dependent Claim
37 words
The method of making an integrated circuit as recited in claim 7, wherein the wafer is further characterized by having an working layer (1) and a handle layer (2), the handle layer having the oxide layer thereon.
Claim 9
Dependent Claim
28 words
The method of making an integrated circuit as recited in claim 8, wherein the working layer is insulated from the handle layer by a layer of oxide (3).
Claim 10
Dependent Claim
33 words
The method of making an integrated circuit as recited in claim 9, wherein the polishing step uses an etchant that selectively removes the material of the wafer relative to the oxide layer thereon.
Claim 11
Dependent Claim
24 words
The method of making an integrated circuit as recited in claim 10, further characterized by the step of: removing the oxide layer on wafer.
Claim 12
Dependent Claim
24 words
The method of making an integrated circuit as recited in claim 11, wherein the working layer and the handle layer are comprised of silicon.
Claim 13
Independent Claim
59 words
A method of planarizing bonded wafers (5) having an working layer (1) and a handle layer (2), CHARACTERIZED BY THE STEPS OF: forming an oxide layer (4) on the handle layer; grinding the wafer to a predetermined thickness; and polishing the ground wafer to form a substantially planar wafer; wherein the the oxide layer remains after the polishing step.
Claim 14
Dependent Claim
32 words
The method of planarizing bonded wafers as recited in claim 13, wherein the polishing step uses an etchant that selectively removes the material of the wafer relative to the oxide layer thereon.
Claim 15
Dependent Claim
24 words
The method of planarizing bonded wafers as recited in claim 14, further characterized by the step of: removing the oxide layer on the wafer.
Claim 16
Dependent Claim
26 words
The method of planarizing bonded wafers as recited in claim 15, wherein the working layer is insulated from the handle layer by a layer of oxide.
Claim 17
Dependent Claim
23 words
The method of planarizing bonded wafers as recited in claim 16, wherein the working layer and the handle layer are comprised of silicon.
References Cited (Backward Citations)
No citation records indexed.
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