Imager wafer level module and method of fabrication and use

• US 20090206431A1
• Filed: 02/20/2008
• Published: 08/20/2009
• Est. Priority Date: 02/20/2008
• Status: Abandoned Application

• Current Assignee: Aptina Imaging Corporation (ON Semiconductor Corporation)
• Original Assignee: Micron Technology, Inc.
• Inventors: Bolken, Todd O., Vanam, Kiran
• Application Number:
  US12/071,399
• Publication Number:
  US 20090206431A1
• Time in Patent Office: Days
• US Class Current: 257/432
• CPC Class Codes: G02B 7/02 for lenses supports for magnifying lenses G02B25/002
• CPC Class Codes: H01L 27/14618 Containers
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H01L 27/14687 Wafer level processing
• 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 2924/0002 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
• CPC Class Codes: H01L 31/0232 Optical elements or arrangements associated with the device H01L31/0236 takes precedence; for photovoltaic cells H01L31/054; for photovoltaic modules H02S40/20
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices

Abstract

Imager wafer level modules, methods of assembly for imager wafer level modules, and systems containing imager wafer level modules. An imager die and an optic lens stack are combined to form a module assembly. The module assembly is combined with a molded plastic, laminated plastic, or metallic interposer to form an imager wafer level module capable of assembly using industry standard equipment sets for all processing, and capable of being used with various imaging systems.

Claims

1. A method of assembling an imager wafer level module comprising:

forming a module assembly comprising an imager die and optic lens stack;

fastening the module assembly to the interposer using a first fastening substance;

fastening a housing to the module assembly using a second fastening substance; and

fastening the housing to the interposer using a third fastening substance.

2. The method of claim 1, wherein the imager die is assembled by:

mounting a plurality of imagers on a wafer; and

dicing the plurality of imagers into a plurality of imager dies.

3. The method of claim 1, wherein the optic lens stack is assembled by:

mounting a plurality of optic lenses on a wafer; and

dicing the plurality of optic lenses into a plurality of optic lens stacks.

4. The method of claim 1, wherein forming a module assembly comprises:

forming a plurality of imager dies on a first wafer;

forming a plurality of optic lens stacks on a second wafer;

arranging the first and second wafers such that light may pass through the plurality of optic lens stacks to an imager of each of the plurality of imager dies; and

fastening the first and second wafers together.

5. The method of claim 1, wherein forming a module assembly comprises:

selecting an imager die and placing the imager die on a carrier;

selecting an optic lens stack and placing the optic lens stack on the imager die; and

fastening the optic lens stack to the imager die with a fastening substance.

6. The method of claim 1, wherein the second and third fastening substances are selected from the group consisting of solder paste and conductive epoxy.

7. The method of claim 1 further comprising fastening a light guide to the interposer.

8. The method of claim 1, wherein the interposer is molded to include an interposer light guide.

9. The method of claim 1, wherein the interposer comprises material selected from the group consisting of molded plastic, plastic laminate, and metals.

10. The method of claim 1 further comprising:

applying liquid encapsulation to a perimeter of the imager die;

dispensing a plurality of solder balls to the module assembly; and

separating individual imager wafer level modules.

11. The method of claim 1, wherein the interposer is a molded plastic interposer, the first and third fastening substances are adhesive, the housing is adhered to the molded plastic interposer, and the module assembly is adhered to the molded plastic interposer.

12. The method of claim 1, wherein the interposer is a molded plastic interposer, the first fastening substance comprises adhesive, the third fastening substance comprises solder, the module assembly is adhered to the molded plastic interposer, and the housing is soldered to the molded plastic interposer

13. The method of claim 1, wherein the interposer is plastic laminate, the first fastening substance comprises a first solder paste pattern, the third fastening substance comprises a second solder paste pattern, the module assembly is soldered to the plastic laminate interposer with the first solder paste pattern, and the housing is soldered to the plastic laminate interposer with the second solder paste pattern.

14. The method of claim 1, wherein the interposer is plastic laminate, the first fastening substance comprises an adhesive, the third fastening substance comprises a solder paste pattern, the module assembly is adhered to the plastic laminate interposer, and the housing is soldered to the plastic laminate interposer.

15. The method of claim 1, wherein the interposer is metallic, the first fastening substance comprises a first solder paste pattern, the third fastening substance comprises a second solder paste pattern, the module assembly is soldered to the metallic interposer with the first solder paste pattern, and the housing is soldered to the metallic interposer with the second solder paste pattern.

16. The method of claim 1, wherein the interposer is metallic, the first fastening substance comprises an adhesive, the third fastening substance comprises a solder paste pattern, the module assembly is adhered to the metallic interposer, and the housing is soldered to the metallic interposer.

17. An apparatus comprising:

an imager die assembly;

an optic lens stack fastened to the imager die by a first fastening substance;

a housing fastened to the imager die by a second fastening substance; and

an interposer fastened to the housing by a third fastening substance, the interposer fastened to the optic lens stack by a fourth fastening substance.

18. The apparatus of claim 17, wherein the second fastening substance is selected from the group consisting of solder paste and conductive epoxy.

19. The apparatus of claim 17 further comprising:

a plurality of solder balls fastened to the imager die assembly; and

liquid encapsulation encapsulating the perimeter of the imager die assembly.

20. The apparatus of claim 17, wherein the interposer comprises material selected from the group consisting of molded plastic, plastic laminate, and metals.

21. The apparatus of claim 17, wherein the housing further comprises a plurality of tabs for attaching the housing to the imager die.

22. The apparatus of claim 21, wherein the housing further comprises ground pad solder control plating and interposer attach solder control plating.

23. The apparatus of claim 17, wherein the interposer further comprises:

an aperture;

an interposer light guide;

lens attach solder control plating;

housing attach solder control plating; and

an interposer singulation track.

24. A camera system, comprising:

an imaging device comprising an imager wafer level module assembly comprising;

an imager die assembly;

an optic lens stack fastened to the imager die by a first fastening substance;

a housing fastened to the imager die by a second fastening substance; and

an interposer fastened to the optic lens stack by a third fastening substance, the interposer fastened to the housing by a fourth fastening substance.

25. The system of claim 24, wherein the interposer is selected from the group consisting of a molded plastic interposer, a plastic laminate interposer, and a metallic interposer.