Optical semiconductor device

• US 7,202,507 B2
• Filed: 06/23/2004
• Issued: 04/10/2007
• Est. Priority Date: 06/24/2003
• Status: Active Grant

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Isokawa, Shinji
• Primary Examiner(s): LOUIE, WAI SING
• Application Number:
  US10/875,599
• Publication Number:
  US 20050040405A1
• Time in Patent Office: 1,021 Days
• Field of Search: None
• US Class Current: 257/95
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• 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 2924/00014 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 2933/0091 Scattering means in or on the semiconductor body or semiconductor body package H01L33/22 takes precedence
• CPC Class Codes: H01L 33/54 having a particular shape

Abstract

An optical semiconductor device includes an optical semiconductor chip and a light permeable member covering the optical semiconductor chip. The light permeable member has a light emitting surface for emitting light coming out from the optical semiconductor chip to the outside. The light emitting surface includes a plurality of standing surfaces standing in a second direction which intersects a first direction in which the light emitting surface spreads.

Claims

1. An optical semiconductor device comprising:

an optical semiconductor chip capable of emitting light, the optical semiconductor chip having an upper surface and a side surface; and

an encapsulating light permeable member covering the optical semiconductor chip in contact with said upper and side surfaces and having a light emitting surface for emitting light coming out from the optical semiconductor chip to outside, the light emitting surface being larger than said upper surface of the semiconductor chip;

wherein the light emitting surface is irregular and includes a plurality of standing surfaces standing in a second direction which intersects a first direction in which the light emitting surface spreads; and

wherein each of the standing surfaces has a height and a width which are determined to satisfy an inequality H<

W×

tanα

c, wherein H is the height of the projection, W is the width of the projection, and α

c is a total reflection critical angle of the light permeable member.

2. The optical semiconductor device according to claim 1, wherein the light emitting surface includes a plurality of non-standing flat surfaces extending in the first direction.

3. The optical semiconductor device according to claim 2, wherein the light permeable member is formed with a plurality of projections standing in the second direction, the projections including a plurality of side surfaces providing the standing surfaces and top surfaces providing part of the non-standing surfaces, the standing surfaces extending perpendicularly to the first direction.

4. The optical semiconductor device according to claim 3, wherein other part of the non-standing surfaces is provided by a region positioned between the projections.

5. The optical semiconductor device according to claim 3, wherein the plurality of projections are arranged in a matrix at the light emitting surface, each of the projections being in a form of a rectangular parallelepiped having a horizontal top surface and four vertical side surfaces.

6. The optical semiconductor device according to claim 1, further comprising a reflector surrounding the light permeable member, and an insulating substrate for mounting the optical semiconductor chip, the light permeable member and the reflector, wherein the reflector includes a reflecting surface for reflecting light coming out from the optical semiconductor chip toward the light emitting surface, and wherein the substrate is formed with a conductor portion electrically connected to the optical semiconductor chip.

7. The optical semiconductor device according to claim 1, wherein each of the projections is in a form of a triangular prism having a horizontal top surface and three vertical side surfaces.

8. The optical semiconductor device according to claim 1, wherein each of the projections is columnar with a horizontal top surface and a cylindrical side surface.

9. The optical semiconductor device according to claim 1, wherein each of the projections is elongated in a same horizontal direction.