Package-ready light-sensitive integrated circuit and method for its preparation

• US 6,876,052 B1
• Filed: 05/12/2000
• Issued: 04/05/2005
• Est. Priority Date: 05/12/2000
• Status: Expired due to Term

• Current Assignee: National Semiconductor Corporation (Texas Instruments, Inc.)
• Original Assignee: National Semiconductor Corporation (Texas Instruments, Inc.)
• Inventors: Tai, Ching K.
• Primary Examiner(s): Thomas, Tom
• Assistant Examiner(s): Lee, Eugene
• Application Number:
  US09/570,181
• Time in Patent Office: 1,789 Days
• Field of Search: 257/433, 257/435, 257/436, 257/778, 257/787, 257/788, 257/737, 257/738, 257/686, 438/48, 438/64, 438/108
• US Class Current: 257/433
• CPC Class Codes: H01L 2224/29099 Material
• CPC Class Codes: H01L 27/14618 Containers
• CPC Class Codes: H01L 27/14634 Assemblies, i.e. Hybrid structures
• CPC Class Codes: H01L 27/14636 Interconnect structures
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00013 Fully indexed content
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 31/0203 Containers; Encapsulations , e.g. encapsulation of photodiodesfor photovoltaic devices H01L31/048; for organic photosensitive devices H10K30/80

Abstract

A package-ready light-sensitive integrated circuit and process for preparing a light-sensitive semiconductor substrate for packaging that provide for a reduced exposure of a light-sensitive integrated circuit to light. The package-ready light-sensitive integrated circuit includes a semiconductor substrate (e.g., a silicon wafer) with an upper surface and a lower surface and lateral edges, an individual light-sensitive integrated circuit formed in and on the upper surface of the semiconductor substrate, and an opaque material layer covering the lower surface and lateral edges of the semiconductor substrate. The opaque material layer prevents light from entering the semiconductor substrate and interfering with operation of the light-sensitive integrated circuit. The process includes first providing at least one semiconductor substrate with a plurality of light-sensitive integrated circuits formed in and on its upper surface. Next, the semiconductor substrate(s) is diced to form individual light-sensitive integrated circuits, each of which has a semiconductor substrate lower surface and semiconductor substrate lateral edges. The individual light-sensitive integrated circuits are then transferred into a magazine and their semiconductor substrate lower surface and semiconductor substrate lateral edges covered (for example by injection molding) with an opaque material (e.g., an opaque molding compound or opaque epoxy) to form an opaque material layer thereon, thereby forming coated light-sensitive integrated circuits. The coated light-sensitive integrated circuits are then removed from the magazine.

Claims

1. A package-ready light-sensitive integrated circuit comprising:

a semiconductor substrate having an upper surface, a lower surface, lateral edges, and an individual light-sensitive integrated circuit formed on the upper surface of the semiconductor substrate; and

an opaque material layer covering the lower surface and lateral edges of the semiconductor substrate, the opaque material layer not being formed over any portion of the upper surface of the semiconductor substrate when the upper surface is positioned above the lower surface.

2. The package-ready light-sensitive integrated circuit of claim 1 and further comprising a plurality of solder bumps attached to make electrical connections with the individual light-sensitive integrated circuit.

3. The package-ready light-sensitive integrated circuit of claim 1, wherein the opaque material layer is formed of opaque molding compound.

4. The package-ready light-sensitive integrated circuit of claim 1, wherein the opaque material layer is formed of opaque epoxy.

5. The package-ready light-sensitive integrated circuit of claim 1, wherein the opaque material layer is formed of opaque ink.

6. The package-ready light-sensitive integrated circuit of claim 1, wherein the opaque material layer is formed of opaque paint.

7. The package-ready light-sensitive integrated circuit of claim 1, wherein the thickness of the opaque material layer is in the range of 0.003 inches to 0.011 inches.

8. A package-ready light-sensitive integrated circuit comprising:

a semiconductor substrate having an upper surface, a lower surface, lateral edges, and an individual light-sensitive integrated circuit formed on the upper surface of the semiconductor substrate;

an opaque material layer covering the lower surface and lateral edges of the semiconductor substrate, the opaque material layer not being formed over any portion of the upper surface of the semiconductor substrate when the upper surface is positioned above the lower surface;

a plurality of solder bumps attached to make electrical connections with the individual light-sensitive integrated circuit; and

a light barrier metal layer formed over the upper surface of the semiconductor substrate when the upper surface is positioned above the lower surface, the light barrier metal layer having a plurality of openings, the solder bumps being formed through the openings, the light barrier metal layer being spaced apart and electrically isolated from the solder bumps.

9. A semiconductor device comprising:

a semiconductor substrate having an upper surface, a lower surface, lateral edges, and an integrated circuit formed on the upper surface of the semiconductor substrate;

a plurality of solder bumps connected to make electrical connections with the integrated circuit, a peripheral solder bump being formed such that no other solder bump lies between the peripheral solder bump and a lateral edge; and

an opaque material layer covering the lower surface and lateral edges of the semiconductor substrate, the opaque material layer not being formed over a peripheral region of the upper surface of the semiconductor substrate when the upper surface is positioned above the lower surface, the peripheral region being spaced apart from the lateral edge, and lying between the peripheral solder bump and the lateral edge.

10. A semiconductor device comprising:

a semiconductor substrate having an upper surface, a lower surface, lateral edges, and an integrated circuit formed on the upper surface of the semiconductor substrate;

a plurality of solder bumps connected to make electrical connections with the integrated circuit, a peripheral solder bump being formed such that no other solder bump lies between the peripheral solder bump and a lateral edge;

an opaque material layer covering the lower surface and lateral edges of the semiconductor substrate, the opaque material layer not being formed over a peripheral region of the upper surface of the semiconductor substrate when the upper surface is positioned above the lower surface, the peripheral region being spaced apart from the lateral edge, and lying between the peripheral solder bump and the lateral edge; and

a light-barrier metal layer formed over the upper surface of the semiconductor substrate when the upper surface is positioned above the lower surface, the light barrier metal layer having a plurality of openings, the solder bumps being formed through the openings, the light barrier metal layer being spaced apart and electrically isolated from the solder bumps.

11. A semiconductor device comprising:

a semiconductor structure having a first surface, a second surface spaced apart from the first surface, a plurality of side walls that contact the first and second surfaces, and an individual light-sensitive integrated circuit formed on the first surface of the semiconductor structure; and

an opaque material layer contacting the second surface and the side walls of the semiconductor structure, the opaque material layer not being formed over any portion of the first surface of the semiconductor structure when the first surface is positioned above the second surface.

12. The semiconductor device of claim 11 and further comprising a plurality of solder bumps attached to make electrical connections with the individual light-sensitive integrated circuit.

13. A semiconductor device comprising:

a semiconductor structure having a first surface, a second surface spaced apart from the first surface, a plurality of side walls that contact the first and second surfaces, and an individual light-sensitive integrated circuit formed on the first surface of the semiconductor structure;

an opaque material layer contacting the second surface and the side walls of the semiconductor structure, the opaque material layer not being formed over any portion of the first surface of the semiconductor structure when the first surface is positioned above the second surface;

a plurality of solder bumps attached to make electrical connections with the individual light-sensitive integrated circuit; and

a light barrier metal layer formed over the first surface of the semiconductor substrate when the first surface is positioned above the second surface, the light barrier metal layer having a plurality of openings, the solder bumps being formed through the openings, the light barrier metal layer being spaced apart and electrically isolated from the solder bumps.

14. A semiconductor device comprising:

a semiconductor structure having a first surface, a second surface spaced apart from the first surface, a plurality of side walls that contact the first and second surfaces, and an individual light-sensitive integrated circuit formed on the first surface of the semiconductor structure; and

an opaque material layer contacting the second surface and the side walls of the semiconductor structure, the opaque material layer not being formed under any portion of the first surface of the semiconductor structure when the first surface is positioned below the second surface.

15. The semiconductor device of claim 14 and further comprising a plurality of solder bumps attached to make electrical connections with the individual light-sensitive integrated circuit.

16. A semiconductor device comprising:

a semiconductor structure having a first surface, a second surface spaced apart from the first surface, a plurality of side walls that contact the first and second surfaces, and an individual light-sensitive integrated circuit formed on the first surface of the semiconductor structure;

an opaque material layer contacting the second surface and the side walls of the semiconductor structure, the opaque material layer not being formed under any portion of the first surface of the semiconductor structure when the first surface is positioned below the second surface;

a plurality of solder bumps attached to make electrical connections with the individual light-sensitive integrated circuit; and

a light barrier metal layer formed under the first surface of the semiconductor substrate when the first surface is positioned below the second surface, the light barrier metal layer having a plurality of openings, the solder bumps being formed through the openings, the light barrier metal layer being spaced apart and electrically isolated from the solder bumps.

17. A semiconductor device comprising:

a semiconductor structure having a first surface, a second surface spaced apart from the first surface, a plurality of side walls that contact the first and second surfaces, and an integrated circuit formed on the first surface of the semiconductor structure;

a metal layer formed on the first surface of the semiconductor structure, the metal layer having a plurality of openings that expose the integrated circuit; and

a plurality of solder bumps formed through the openings such that each opening has a solder bump formed through the opening to make an electrical connection with the integrated circuit.

18. The semiconductor device of claim 17 wherein the solder bumps have sizes, and the openings have diameters that are a function of the sizes of the solder bumps formed in the openings.

19. The semiconductor device of claim 17 wherein the solder bumps are electrically isolated from the metal layer.

20. The semiconductor device of claim 17 wherein the metal layer blocks substantially all light from passing through the first surface.

21. The semiconductor device of claim 17 and further comprising an opaque material layer that contacts the second surface and the side walls of the semiconductor structure.