Low cost CCD packaging

• US 6,268,231 B1
• Filed: 10/14/1999
• Issued: 07/31/2001
• Est. Priority Date: 04/08/1996
• Status: Expired due to Term

• Current Assignee: Semiconductor Components Industries LLC (ON Semiconductor Corporation)
• Original Assignee: Eastman Kodak Company
• Inventors: Wetzel, Keith E.
• Primary Examiner(s): POTTER, ROY KARL
• Application Number:
  US09/417,747
• Time in Patent Office: 656 Days
• Field of Search: 438/48, 438/66, 438/67, 438/73, 438/80, 438/116, 438/123
• US Class Current: 438/48
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• 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: H05K 1/0271 Arrangements for reducing stress or warp in rigid printed circuit boards, e.g. caused by loads, vibrations or differences in thermal expansion
• CPC Class Codes: H05K 1/189 characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence

Abstract

A packaging solution for CCD devices and other opto-electronic applications that offers a lower cost, automated assembly process. A package made of a moldable plastic material with low moisture permeability, and high dimensional stability by employing materials such as liquid crystal polymer. While relatively high cost plastic materials may be used, the overall cost is expected to be substantially lower than a corresponding ceramic package. An interconnect circuit pattern is then be formed on the plastic using one of a variety of plating options known in the circuit board, and in the molded interconnect industry. The ability to mold a flexible circuits into the package results from the use of these materials. Conductors of standard materials in the circuit board industry; e.g., copper with selective nickel and gold plating are employed on a non reflective substrate surface. The CCD sensor is mounted to this plastic substrate and connected to the conductive pattern using standard wire bonding processes. In order to support a transparent cover glass which protects the CCD sensor, a supporting ring frame can be molded into the plastic. This support ring would surround the CCD sensor, and provide a means of supporting the cover glass. The plastic substrate would then be interconnected to the external world via the integral flexible circuit. Standard zero insertion flexible circuit connectors would be the preferred method of connecting the flexible circuit to the system electronics. The use of anisotropic adhesives or traditional butt joint soldering techniques might also be used depending upon the application.

Claims

1. A method for packaging a charge coupled device (CCD) comprising the steps of:

providing a flexible circuit board having a substrate with a plurality of conductors formed, thereon;

providing a base structure on a first side of the flexible circuit board;

providing a ring frame on a second side of the flexible circuit board opposite from and cooperating with the base structure, the ring frame having a cavity formed, therein, such that the CCD can be held within the cavity;

providing an electrical interface between the CCD within the cavity and the conductors on the substrate of the flexible circuit;

placing the CCD within the cavity such that it is in juxtaposition for be electrical connection with the electrical interface; and

isolating the CCD from ambient conditions while allowing light to pass and become incident upon the CCD.

2. The method of claim 1 wherein the steps of providing the frame, the base and the substrate further comprises providing them made from a plastic material.

3. The method of claim 1 wherein the steps of providing the frame, the base and the substrate further comprises providing them made from a non-reflective material.

4. The method of claim 1 wherein the steps of providing the frame, the base and the substrate further comprises providing them made from a material having low moisture permeability.