IMAGING APPARATUS HAVING PHOTOSENSOR AND MANUFACTURING METHOD OF THE SAME

• US 20110291212A1
• Filed: 05/25/2011
• Published: 12/01/2011
• Est. Priority Date: 05/28/2010
• Status: Active Grant

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Mihara, Ichiro, Wakabayashi, Takeshi
• Granted Patent: US 8,507,309 B2
• Time in Patent Office: Days
• US Class Current: 257/432
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 27/14618 Containers
• CPC Class Codes: H01L 27/14683 Processes or apparatus peculiar to the manufacture or treatment of these devices or parts thereof not peculiar thereto H01L21/00
• CPC Class Codes: H01L 27/14687 Wafer level processing

Abstract

A photosensor comprises a photoelectric conversion device region and a connection pad on the lower surface of a semiconductor substrate, and also comprises a wiring line connected to the connection pad via insulating film under the semiconductor substrate, and a columnar electrode as an external connection electrode connected to the wiring line. As a result, as compared with the case where the photoelectric conversion device region and the connection pad connected to the photoelectric conversion device region are formed on the upper surface of the semiconductor substrate, a piercing electrode for connecting the connection pad and the wiring line does not have to be formed in the semiconductor substrate. Thus, the number of steps can be smaller, and a fabrication process can be less restricted.

Claims

1. An imaging apparatus comprising:

a lens unit which light enters from one surface thereof; and

a photosensor provided on the other surface of the lens unit, the photosensor comprising a semiconductor substrate which the light exiting from the lens unit enters from one surface thereof, and a photoelectric conversion device and a connection pad which are provided on the other surface of the semiconductor substrate.

2. The imaging apparatus according to claim 1, further comprising a visible light transmitting material having a visible light transmission factor of 90% or more and having an infrared transmission factor of 10% or less between the semiconductor substrate and the lens unit.

3. The imaging apparatus according to claim 2, wherein the visible light transmitting material includes one of materials selected from the group consisting of glass, a methacrylic resin, a fluorene resin, a cycloolefin polymer, an epoxy resin, polyethylene, polystyrene, an AS resin, polyethylene terephthalate, a vinylidene chloride resin, polycarbonate, and a light-blocking ceramic.

4. The imaging apparatus according to claim 1, wherein the photosensor comprises an insulating film provided on the other surface of the semiconductor substrate, a wiring line provided on the lower surface of the insulating film to be connected to the connection pad, a columnar electrode provided under a land of the wiring line, and a sealing film provided around the columnar electrode under the wiring line and under the insulating film.

5. The imaging apparatus according to claim 4, wherein a solder ball is provided under the columnar electrode of the photosensor.

6. The imaging apparatus according to claim 1, wherein the photosensor comprises an insulating film provided on the other surface of the semiconductor substrate, a wiring line which is provided on the lower surface of the insulating film to be connected to the connection pad and which includes a land as an external connection electrode, and a sealing film provided in a region under the insulating film including the wiring line except for the land of the wiring line.

7. The imaging apparatus according to claim 6, wherein a solder ball is provided under the land of the wiring line of the photosensor.

8. The imaging apparatus according to claim 1, wherein a lens constituting the lens unit is equipped with an infrared cut filter that only transmits 10% of infrared rays or less.

9. An imaging apparatus manufacturing method comprising:

disposing a lens unit on the other surface of a semiconductor wafer of a photosensor, a photoelectric conversion device region and a connection pad being provided on one surface of the semiconductor wafer.

10. The imaging apparatus manufacturing method according to claim 9, wherein a visible light transmitting material having a visible light transmission factor of 90% or more and having an infrared transmission factor of 10% or less is provided between the semiconductor substrate and the lens unit.

11. The imaging apparatus manufacturing method according to claim 10, wherein the visible light transmitting material includes one of materials selected from the group consisting of glass, a methacrylic resin, a fluorene resin, a cycloolefin polymer, an epoxy resin, polyethylene, polystyrene, an AS resin, polyethylene terephthalate, a vinylidene chloride resin, polycarbonate, and a light-blocking ceramic.

12. The imaging apparatus manufacturing method according to claim 9, wherein an external connection electrode connected to the connection pad is formed, and the semiconductor wafer is diced to obtain imaging apparatuses.

13. The imaging apparatus manufacturing method according to claim 10, further comprising forming a solder ball under the external connection electrode before disposing the visible light transmitting material.

14. The imaging apparatus manufacturing method according to claim 13, further comprising grinding the upper side of the semiconductor wafer after forming the solder ball.

15. The imaging apparatus manufacturing method according to claim 14, further comprising affixing a protective tape to the side of the solder ball of the semiconductor wafer before grinding the upper side of the semiconductor wafer after forming the solder ball, and detaching the protective tape after disposing the lens unit.

16. The imaging apparatus manufacturing method according to claim 12, wherein an insulating film is provided on the other surface of the semiconductor substrate, a wiring line is provided on the lower surface of the insulating film to be connected to the connection pad, a columnar electrode as the external connection electrode is provided under a land of the wiring line, and a sealing film is provided around the columnar electrode under the insulating film including the wiring line.

17. The imaging apparatus manufacturing method according to claim 12, wherein an insulating film is provided on the other surface of the semiconductor substrate, a wiring line is provided on the lower surface of the insulating film to be connected to the connection pad and includes a land as the external connection electrode, and a sealing film is provided in a region under the insulating film including the wiring line except for a land of the wiring line.

18. The imaging apparatus manufacturing method according to claim 9, wherein a lens constituting the lens unit is equipped with an infrared cut filter that only transmits 10% of infrared rays or less.

19. The imaging apparatus manufacturing method according to claim 10, wherein each photosensor formation region is electrically tested, and when there is a photosensor formation region judged to be defective, the visible light transmitting material and the lens unit are not disposed in the photosensor formation region judged to be defective.