Optical coupling device

• US 10,008,626 B2
• Filed: 03/04/2016
• Issued: 06/26/2018
• Est. Priority Date: 09/04/2015
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Muranaka, Tetsuya
• Primary Examiner(s): Lee, Eugene
• Application Number:
  US15/061,999
• Publication Number:
  US 20170069781A1
• Time in Patent Office: 844 Days
• 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 2933/0033 relating to semiconductor body packages
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• 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 31/162 the light source being a semiconductor device with at least one potential-jump barrier or surface barrier, e.g. a light emitting diode
• CPC Class Codes: H01L 31/173 formed in, or on, a common substrate
• CPC Class Codes: H01L 33/005 Processes
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

An optical coupling device includes a light-emitting element, a light-receiving element that faces the light-emitting element, a lead frame that has a first surface on which the light-emitting element is provided and a second surface facing the first surface, a first covering material that covers the light-emitting element, a second covering material that covers the first covering material, the light-receiving element, and the lead frame, and a third covering material that covers the second covering material. At least one of first bonding strength between the second covering material and the third covering material and second bonding strength between the second covering material and the second surface is lower than third bonding strength between the first covering material and the second covering material.

Claims

1. An optical coupling device, comprising:

a light-emitting element facing a light-receiving element;

a first lead frame portion having a first upper surface on which the light-emitting element is provided and a second lower surface on a side of the first lead frame portion opposite the first upper surface;

a first material on the first upper surface covering the light-emitting element;

a second material surrounding the first material, the light-receiving element, and the first lead frame portion; and

a third material surrounding the second material, wherein

at least one of an adhesion strength between the second material and the third material and an adhesion strength between the second material and the second lower surface is less than an adhesion strength between the first material and the second material.

2. The device according to claim 1, wherein a mold releasing agent is between the second material and the third material.

3. The device according to claim 2, wherein the mold releasing agent is between the second material and the third material in a region facing the second lower surface.

4. The device according to claim 3, wherein the mold releasing agent is an organic material.

5. The device according to claim 4, wherein the organic material includes a long chain fatty acid.

6. The device according to claim 1, wherein a mold releasing agent is disposed at an interface between the second material and the second lower surface.

7. The device according to claim 6, wherein the mold releasing agent comprises a long-chain fatty acid.

8. The device according to claim 1, wherein the adhesion strength between the second material and the second lower surface is less than an adhesion strength between the second material and the first upper surface.

9. The device according to claim 8, wherein a surface roughness of the second lower surface is greater than a surface roughness of the first upper surface.

10. The device according to claim 1, wherein the adhesion strength between the second material and the third material is less than the adhesion strength between the second material and the second lower surface.

11. The device according to claim 1, wherein an adhesion strength between the second material and the first upper surface is less than the adhesion strength between the first material and the second material.

12. An optical coupling device, comprising:

a light-emitting element facing a light-receiving element;

a first lead frame portion having a first upper surface on which the light-emitting element is provided and a second lower surface opposite the first upper surface;

a silicone resin on the first upper surface and covering the light-emitting element;

a transparent inner molding resin surrounding the silicone resin, the light-receiving element, and the first lead frame portion;

a light shielding outer molding resin surrounding the transparent inner molding resin; and

an organic material, wherein the organic material is disposed at a position that is one of between the transparent inner molding resin and the light shielding outer molding resin and between the transparent inner molding resin and the second lower surface.

13. The optical coupling device according to claim 12, wherein the organic material is between the transparent inner molding resin and the light shielding outer molding resin and between the transparent inner molding resin and the second lower surface.

14. The optical coupling device according to claim 12, wherein the organic material is between the transparent inner molding resin and the light shielding outer molding resin.

15. The optical coupling device according to claim 12, wherein the organic material is disposed at an interface between the transparent inner molding resin and the second lower surface.

16. The optical coupling device according to claim 12, wherein a surface roughness of the second lower surface is greater than a surface roughness of the first upper surface.

17. The optical coupling device according to claim 12, further comprising:

a bonding wire within the silicone resin electrically connecting the light-emitting element to the first upper surface of the first lead frame portion.