Compact image sensor

• US 5,051,802 A
• Filed: 08/06/1990
• Issued: 09/24/1991
• Est. Priority Date: 01/22/1988
• Status: Expired due to Term

• Current Assignee: Thomson-CSF (Thales SA)
• Original Assignee: Thomson-CSF (Thales SA)
• Inventors: Chabbal, Jean, Prost, Roger
• Primary Examiner(s): Hille, Rolf
• Assistant Examiner(s): FAHMY, WAEL M
• Application Number:
  US07/563,826
• Time in Patent Office: 414 Days
• Field of Search: 357/30 D, 357/30 K, 357/30 L, 357/30 M, 357/30 Q, 357/74, 357/74 A, 357/74 B, 357/74 C
• US Class Current: 257/434
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 27/14618 Containers
• CPC Class Codes: H01L 2924/01014 Silicon [Si]
• CPC Class Codes: H01L 31/02005 for device characterised by at least one potential jump barrier or surface barrier
• 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 compact image sensor is disclosed. This sensor comprises an insulating, imperviously sealed package, provided with a window which is transparent to light rays and is located on a front face. The inside of the package contains a stack arrangement which comprises, between the back of the package and the window, an insulating support, a set of photosensitive elements with a semiconducting substrate, surrounded by contacts. Connection terminals go through the back of the package and the insulating support. Connection means are interposed between these contacts and the ends of the terminals. The light rays are received by the photosensitive elements after they have crossed the semiconducting substrate which is thinned down beforehand. This arrangement of the photosensitive elements, the substrate and the connection means enables an appreciable increase in the area of the photosensitive surface and in the number of connection terminals, without an increase in the area of the front surface of the sensor.

Claims

1. A compact arrayed image sensor, comprising:

an imperviously sealed package made of an electrically insulating material, said package having a front face provided with a transparent window;

an insulating support interposed between said front and rear face;

an array of photosensitive elements on a monocrystalline semiconductor substrate, wherein said semiconductor substrate is interposed between said window and said insulating support, said semiconductor substrate facing said window, and said array of photosensitive elements facing said insulating support, oriented such that said photosensitive elements receive light rays that have gone through the window and through the substrate;

electrical contacts for connection with said photosensitive elements, said contacts being located on said semiconductor substrate;

connection terminals which go through the insulating support and through the rear face of the package, said connection terminals having respective ends, an internal end located on the inside, and an external end located on the outside of said impervious package.

2. An image sensor according to claim 1, wherein the connection means comprise spacers made of an electrically conductive material, respectively interposed between the ends of the terminals and the corresponding contacts, these spacers being in contact with these ends and these terminals.

3. A sensor according to claim 1, wherein said spacers are indium balls.

4. A sensor according to claim 1, wherein said spacers are formed by a conductive bonder.

5. A sensor according to claim 1, wherein the connection means comprise an insulating sheet including zones of conductive material, respectively located so as to face said contacts and the corresponding ends of said terminals.

6. A sensor according to claim 5, wherein said conducting material is a metal.

7. A compact arrayed image sensor comprising an imperviously sealed package, said package having a rear face, and a front face provided with a transparent window;

and

array of photosensitive elements on a monocrystalline semiconductor substrate wherein said substrate being at least partially transparent to the light radiation to be directed, said semiconductor substrate facing said window and said array facing said rear face such that light radiation to be detected passes through said substrate, said semiconductor substrate provided with contact pads for electrical connection with said photosensitive elements;

said sensor further comprising connecting pins in electrical contact with said contact pads, said pins projecting through the rear face of the package.