US6548323B1
Expired / Lapsed
US
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Method of preparing light-sensitive integrated circuits for packaging
Assignee: National Semiconductor Corp
•
Filing: 2000-07-31
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Granted: 2003-04-15
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Expires: 2020-07-31
Abstract
Abstract A process for preparing a light-sensitive integrated circuit (IC) for packaging that provides a reduced exposure of the light-sensitive IC to light. The process includes providing a semiconductor substrate (e.g., a silicon wafer) with a plurality of light-sensitive ICs formed in/on its upper surface. The lower surface is optionally coated with opaque material. Next, the semiconductor substrate is diced to form individual light-sensitive ICs, each of which has a semiconductor substrate lower surface and semiconductor substrate lateral edges. The semiconductor substrate lateral edges (and optionally backside) are then spray coated with an opaque material (e.g., opaque ink) to form an opaque layer covering the semiconductor substrate lateral edges. The opaque layer prevents light from entering the semiconductor substrate through the lateral edges and interfering with the operation of the light-sensitive IC. The inventive process is simple and inexpensive, employing, for example, piezoelectric injectors to spray coat opaque ink on the semiconductor substrate lateral edges as the individual ICs are conveyed through a pass-through. In addition, processes according to the present invention are independent of the techniques used to manufacture the light-sensitive ICs and, therefore, provide for increased packaging process flexibility and economy.
Inventors
- 👤 Jeffrey R. Perry
- 👤 Michael E. Thomas
- 👤 Robert A. Sabsowitz
- 👤 Reda R. Razouk
- 👤 Aaron G. Simmons
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:39
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/50; H10F71/00; H10F71/136
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
87 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and spray coating the semiconductor substrate lateral edges with an opaque material to form an opaque layer covering the semiconductor substrate lateral edges.
Claim 2
Independent Claim
87 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and spray coating the semiconductor substrate lateral edges with an opaque material to form an opaque layer covering the semiconductor substrate lateral edges.
Claim 3
Dependent Claim
35 words
The method of claim 1 , wherein the spray coating step also includes spray coating the semiconductor substrate lower surface with an opaque material to form an opaque layer covering the semiconductor substrate lower surface.
Claim 4
Dependent Claim
27 words
The method of claim 1 , wherein the spray coating step utilizes an opaque ink to form an opaque ink layer covering the semiconductor substrate lateral edges.
Claim 5
Dependent Claim
24 words
The method of claim 1 , wherein the spray coating step is conducted as the individual light-sensitive integrated circuits are conveyed through a pass-through.
Claim 6
Dependent Claim
22 words
The method of claim 4 , wherein the spray coating step includes conveying the individual light-sensitive integrated circuits with a pick-and-place apparatus.
Claim 7
Dependent Claim
28 words
The method of claim 5 , wherein the spray coating step includes conveying the individual light-sensitive integrated circuits through a pass-through that is integrated with the pick-and-place tool.
Claim 8
Dependent Claim
37 words
The method of claim 4 , wherein the spray coating step is controlled by an optical sensor that detects the presence of a semiconductor substrate lateral edge as the light-sensitive integrated circuit is moved through the passthrough.
Claim 9
Dependent Claim
27 words
The method of claim 4 , wherein the spray coating step is conducted as the individual light-sensitive integrated circuits are conveyed through an adjustable size pass through.
Claim 10
Dependent Claim
18 words
The method of claim 1 , wherein the spray coating step utilizes piezoelectric injectors for the spray coating.
Claim 11
Dependent Claim
26 words
The method of claim 9 further including, following the spray coating step, a step of placing the individual light-sensitive integrated circuit onto a printed circuit board.
Claim 12
Dependent Claim
39 words
The method of claim 1 , wherein the spray coating step is conducted as the individual light-sensitive intergrated circuits are conveyed through a pass-through and the spray coating step utilizes piezoelectric injectors arrayed around a pass-through for spray coating.
Claim 13
Dependent Claim
25 words
The method of claim 1 further including the step of: coating the backside with opaque material, after the providing step and before the dicing step.
Claim 14
Independent Claim
121 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and spray coating the semiconductor substrate lateral edges with an opaque ink to form an opaque layer covering the semiconductor substrate lateral edges, wherein the spray coating step is conducted as the individual light-sensitive integrated circuits are conveyed through a pass-through and wherein the spray coating step utilizes piezoelectric injectors arrayed around the pass-through for spray coating.
Claim 15
Independent Claim
121 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and spray coating the semiconductor substrate lateral edges with an opaque ink to form an opaque layer covering the semiconductor substrate lateral edges, wherein the spray coating step is conducted as the individual light-sensitive integrated circuits are conveyed through a pass-through and wherein the spray coating step utilizes piezoelectric injectors arrayed around the pass-through for spray coating.
Claim 16
Dependent Claim
25 words
The method of claim 13 further including the step of: coating the backside with opaque material, after the providing step and before the dicing step.
Claim 17
Dependent Claim
20 words
The method of claim 13 , wherein the spray coating step also spray coats the backside with an opaque ink.
Claim 18
Independent Claim
87 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and depositing an opaque material on the semiconductor substrate lateral edges to form a deposited opaque layer covering the semiconductor substrate lateral edges.
Claim 19
Independent Claim
87 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and depositing an opaque material on the semiconductor substrate lateral edges to form a deposited opaque layer covering the semiconductor substrate lateral edges.
Claim 20
Dependent Claim
25 words
The method of claim 16 further including the step of: coating the backside with opaque material, after the providing step and before the dicing step.
Claim 21
Dependent Claim
18 words
The method of claim 16 , wherein the depositing step also deposits the opaque material on the backside.
Claim 22
Dependent Claim
27 words
The method of claim 16 , wherein the depositing step utilizes an opaque material selected from the opaque material group consisting of opaque metals and opaque polymers.
Claim 23
Dependent Claim
18 words
The method of claim 16 , wherein the depositing step is conducted using a chemical vapor deposition technique.
Claim 24
Dependent Claim
17 words
The method of claim 16 , wherein the depositing step is conducted using a sputter deposition technique.
Claim 25
Independent Claim
95 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and roughening the semiconductor substrate lateral edges to form roughened lateral edges that reflect incoming light in a manner that minimizes the light reaching the top, light-sensitive surface of the IC.
Claim 26
Independent Claim
95 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and roughening the semiconductor substrate lateral edges to form roughened lateral edges that reflect incoming light in a manner that minimizes the light reaching the top, light-sensitive surface of the IC.
Claim 27
Dependent Claim
30 words
The method of claim 22 further including the step of: coating the backside with opaque material which is resistant to etching, after the providing step and before the dicing step.
Claim 28
Dependent Claim
17 words
The method of claim 22 , wherein the roughening step is conducted using a plasma etching technique.
Claim 29
Dependent Claim
18 words
The method of claim 22 , wherein the roughening step is conducted using a wet chemical etching technique.
Claim 30
Independent Claim
99 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and coating the semiconductor substrate lateral edges with a material to form a material layer of a thickness that provides for destructive interference of incoming light and, thereby, prevents light from entering the semiconductor substrate.
Claim 31
Independent Claim
99 words
A method for preparing light-sensitive integrated circuits for packaging, the method comprising the steps of: providing a semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on an upper surface of the semiconductor substrate; dicing the semiconductor substrate into individual light-sensitive integrated circuits, each of the individual light-sensitive integrated circuits having a semiconductor substrate lower surface and semiconductor substrate lateral edges; and coating the semiconductor substrate lateral edges with a material to form a material layer of a thickness that provides for destructive interference of incoming light and, thereby, prevents light from entering the semiconductor substrate.
Claim 32
Dependent Claim
31 words
The method of claim 26 , wherein the coating step includes coating the semiconductor substrate with a material selected from the group consisting of titanium nitride, silicon nitride, and silicon oxynitride.
Claim 33
Dependent Claim
25 words
The method of claim 26 further including the step of: coating the backside with opaque material, after the providing step and before the dicing step.
Claim 34
Dependent Claim
20 words
The method of claim 26 , wherein the coating step also coats the backside of the substrate with the material.
References Cited (Backward Citations)
US6157019A
Cited
US20020050591A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2006-04-14 | 2006-10-14 | 2007-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-04-14 | 2010-10-14 | 2011-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-04-14 | 2014-10-14 | 2015-04-15 | $7700.00 | Window Closed / Lapsed |