US6261939B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pad metallization over active circuitry
Assignee: Philips Semiconductors Inc
•
Filing: 1999-12-23
•
Granted: 2001-07-17
•
Expires: 2019-12-23
Abstract
Abstract Metal bond pads are formed over active circuitry in a semiconductor chip in a reliable and cost effective manner. According to an example embodiment of the present invention, a metal bond pad is formed over circuitry in the semiconductor chip. A metal layer is formed over the circuitry and the metal bond pad, and a photoresist mask is patterned over the metal layer. The metal layer is etched and the portion of the metal layer not masked with the photoresist is removed. In this manner, additional metal can be formed on the pad site using only one additional mask step, and the thicker metal at the pad site improves the reliability of the chip by providing for a metal cushion at the pad useful in subsequent wire bonding processes.
Inventors
- 👤 Stephen L. Skala
- 👤 Subhas Bothra
- 👤 Emmanuel Demuizon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:36
CPC Classifications
H; H10; H10W; H10W72/00; H10W72/90; H10W72/01; H10W72/012; H10W72/20; H10W72/251; H10W72/29; H10W72/50; H10W72/551; H10W72/552; H10W72/5522; H10W72/59; H10W72/931; H10W72/934; H10W72/951; H10W72/952
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
58 words
A method for manufacturing a semiconductor chip having circuitry, the method comprising: forming a metal bond pad over the circuitry; forming a metal layer over the circuitry and the metal bond pad; patterning a photoresist mask over the metal layer; and etching the metal layer and removing the portion of the metal layer not masked with the photoresist.
Claim 2
Independent Claim
58 words
A method for manufacturing a semiconductor chip having circuitry, the method comprising: forming a metal bond pad over the circuitry; forming a metal layer over the circuitry and the metal bond pad; patterning a photoresist mask over the metal layer; and etching the metal layer and removing the portion of the metal layer not masked with the photoresist.
Claim 3
Dependent Claim
23 words
The method of claim 1 , further comprising forming a diffusion barrier over the metal bond pad prior to forming the metal layer.
Claim 4
Dependent Claim
12 words
The method of claim 2 , wherein the diffusion barrier includes TiN.
Claim 5
Dependent Claim
50 words
The method of claim 2 , wherein forming a diffusion barrier over the metal bond pad includes forming a diffuision barrier layer over and extending beyond the metal bond pad, and wherein etching the metal layer includes removing the portion of the diffusion barrier layer not masked with the photoresist.
Claim 6
Dependent Claim
77 words
The method of claim 3 , wherein forming a diffusion barrier over the metal bond pad includes forming a diffusion barrier layer over and extending beyond the metal bond pad and, prior to forming the metal layer over the circuit side, the method further comprising: patterning a photoresist mask over the diffusion barrier layer; etching the diffusion barrier and removing the portion of the diffusion barrier layer not masked with the photoresist; and removing the photoresist mask.
Claim 7
Dependent Claim
51 words
The method of claim 1 , wherein patterning a photoresist mask includes depositing photoresist material over the bond pad, and wherein etching the metal layer and removing the portion of the metal layer not masked with the photoresist includes removing the portion of the metal layer not over the bond pad.
Claim 8
Dependent Claim
20 words
The method of claim 1 , wherein forming a metal bond pad includes forming a plurality of metal bond pads.
Claim 9
Dependent Claim
53 words
The method of claim 7 , wherein patterning a photoresist mask includes depositing photoresist material over the plurality of bond pads, and wherein etching the metal layer and removing the portion of the metal layer not masked with the photoresist includes removing the portion of the metal layer not over the bond pads.
Claim 10
Dependent Claim
13 words
The method of claim 1 , wherein the metal bond pad includes aluminum.
Claim 11
Dependent Claim
21 words
The method of claim 1 , wherein the metal bond pad and the metal layer include the same type of metal.
Claim 12
Dependent Claim
31 words
The method of claim 1 , wherein the metal layer over the bond pad is of sufficient thickness to prevent the formation of inter-metallic Al/Au during a subsequent wire bonding process.
Claim 13
Dependent Claim
28 words
The method of claim 2 , wherein the diffusion barrier layer is of sufficient thickness to prevent the formation of inter-metallic Al/Au during a subsequent wire bonding process.
Claim 14
Independent Claim
58 words
A method of manufacturing a semiconductor chip, the method comprising: forming a pad having a first metal pad layer, a diffusion barrier layer over the first metal pad layer, and a second metal pad layer over the diffusion barrier; forming a passivation layer over the pad; and etching the passivation layer and exposing the second metal pad layer.
Claim 15
Independent Claim
58 words
A method of manufacturing a semiconductor chip, the method comprising: forming a pad having a first metal pad layer, a diffusion barrier layer over the first metal pad layer, and a second metal pad layer over the diffusion barrier; forming a passivation layer over the pad; and etching the passivation layer and exposing the second metal pad layer.
Claim 16
Dependent Claim
39 words
The method of claim 13 , wherein forming a pad further comprises: patterning a photoresist mask layer over the second metal pad layer; etching the portion of the pad not masked with the photoresist; and removing the photoresist mask.
Claim 17
Dependent Claim
43 words
The method of claim 13 , further comprising forming a photoresist mask layer over the passivation layer prior to etching the passivation layer, wherein the photoresist mask layer is not formed over the portion of the passivation layer that is over the pad.
References Cited (Backward Citations)
US5795818A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-07-16 | 2005-01-15 | 2005-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-07-16 | 2009-01-15 | 2009-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-07-16 | 2013-01-15 | 2013-07-17 | $7700.00 | Window Closed / Lapsed |