Laser diode device

• US 9,008,138 B2
• Filed: 04/09/2013
• Issued: 04/14/2015
• Est. Priority Date: 04/12/2012
• Status: Active Grant

• Current Assignee: OSRAM OLED GMBH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Strauss, Uwe, Tautz, Soenke, Lell, Alfred, Vierheilig, Clemens
• Primary Examiner(s): NGUYEN, TUAN N
• Application Number:
  US13/859,446
• Publication Number:
  US 20130272333A1
• Time in Patent Office: 735 Days
• US Class Current: 372/43.01
• CPC Class Codes: H01S 2301/176 Specific passivation layers on surfaces other than the emission facet
• CPC Class Codes: H01S 5/023 Mount members, e.g. sub-mount members
• CPC Class Codes: H01S 5/0233 Mounting configuration of laser chips
• CPC Class Codes: H01S 5/0235 Method for mounting laser chips
• CPC Class Codes: H01S 5/0237 by soldering
• CPC Class Codes: H01S 5/02375 Positioning of the laser chips
• CPC Class Codes: H01S 5/02461 Structure or details of the laser chip to manipulate the heat flow, e.g. passive layers in the chip with a low heat conductivity
• CPC Class Codes: H01S 5/02469 Passive cooling, e.g. where heat is removed by the housing as a whole or by a heat pipe without any active cooling element like a TEC
• CPC Class Codes: H01S 5/028 Coatings ; Treatment of the laser facets, e.g. etching, passivation layers or reflecting layers
• CPC Class Codes: H01S 5/22 having a ridge or stripe structure

Abstract

A laser diode device is specified, comprising a housing having a mounting part and a laser diode chip based on a nitride compound semiconductor material in the housing on the mounting part, wherein the laser diode chip is mounted directly on the mounting part using a solder layer, and the solder layer has a thickness of greater than or equal to 3 μm.

Claims

1. A laser diode device, comprising:

a housing comprising a mounting part;

a laser diode chip based on a nitride compound semiconductor material disposed on the mounting part, said chip comprising, on a substrate, semiconductor layers with an active layer for generating light and said chip having a radiation coupling-out area with a radiation coupling-out region for emitting the generated light, a rear side area situated opposite the radiation coupling-out area, and side areas connecting the radiation coupling-out area and the rear side area; and

a solder layer disposed between said chip and the mounting part,

wherein the laser diode chip is mounted directly on the mounting part by the solder layer and the solder layer has a thickness of greater than or equal to 3 μ

m; and

wherein the laser diode chip comprises, in an underside facing the mounting part, at least one anchoring element for the solder layer, said at least one anchoring element being formed by a depression or elevation in the underside and spaced from all edges of said chip.

2. The laser diode device according to claim 1, wherein the substrate is an electrically conducting substrate made of crystalline (In,Al,Ga)N.

3. The laser diode device according to claim 1, wherein the laser diode chip is mounted on the mounting part directly with the substrate or with an electrical connection layer on the side of the substrate facing away from the semiconductor layers.

4. The laser diode device according to claim 1, wherein the mounting part has a metal-core circuit board or a main body composed of metal or composed of ceramic.

5. The laser diode device according to claim 1, wherein the housing has a housing part connected to the mounting part, the housing part and the mounting part have a main body composed of copper, and at least the housing part is steel-sheathed.

6. The laser diode device according to claim 1, wherein the housing has a housing cover above the mounting part, said housing cover closing the housing.

7. The laser diode device according to claim 1, wherein the solder layer is composed of a soft solder.

8. The laser diode device according to claim 1, wherein the laser diode chip has a strain that endeavors to convexly deform the underside of the laser diode chip.

9. The laser diode device according to claim 1, wherein the laser diode chip comprises a strain that counteracts at least a concave deformation of the underside of the laser diode chip.

10. The laser diode device according to claim 1, wherein the laser diode chip comprises a plurality of anchoring elements embodied as elevations and/or depressions in the underside and wherein the at least one anchoring element that is spaced from the edge of said chip is one of said plurality of anchoring elements.

11. The laser diode device according to claim 10, wherein wherein the plurality of anchoring elements further includes a further anchoring element embodied as a stepped depression at a chip edge between the underside and the radiation coupling-out area or the rear side area or a side area.

12. The laser diode device according to claim 1, wherein the laser diode chip comprises a metallization on the side areas.

13. The laser diode device according to claim 12, wherein the metallization forms outer sides of the laser diode chip and the solder of the solder layer wets the metallization.

14. The laser diode device according to claim 12, wherein the metallization comprises at least one or a plurality of metals Au, Ti, Pt, Cr, Pd, Ni, Ag, W, Cu.

15. The laser diode device according to claim 12, wherein the laser diode chip comprises, on a top side facing away from the mounting part, at least one depression which extends from the rear side area to the radiation coupling-out area and which is covered with a passivation.

16. The laser diode device according to claim 1, wherein the laser diode chip comprises a metallization on the radiation coupling-out area and/or the rear side area.

17. The laser diode device according to claim 16, wherein the metallization is arranged directly on the semiconductor layers between the semiconductor layers and an optical layer on the radiation coupling-out area and/or the rear side area.

18. The laser diode device according to claim 16, wherein the metallization forms outer sides of the laser diode chip and the solder of the solder layer wets the metallization.

19. A laser diode device, comprising:

a housing comprising a mounting part;

a laser diode chip based on a nitride compound semiconductor material disposed on the mounting part, said chip comprising, on a substrate, semiconductor layers with an active layer for generating light and said chip having a radiation coupling-out area with a radiation coupling-out region for emitting the generated light, a rear side area situated opposite the radiation coupling-out area, and side areas connecting the radiation coupling-out area and the rear side area; and

a solder layer disposed between said chip and the mounting part,

wherein the laser diode chip is mounted directly on the mounting part by the solder layer and the solder layer has a thickness of greater than or equal to 3 μ

m,

wherein the substrate is an electrically conducting substrate made of crystalline (In,Al,Ga)N,

wherein the laser diode chip is mounted on the mounting part directly with the substrate or with an electrical connection layer on the side of the substrate facing away from the semiconductor layers; and

wherein the laser diode chip comprises, in an underside facing the mounting part, at least one anchoring element for the solder layer, said at least one anchoring element being formed by a depression or elevation in the underside and spaced from all edges of said chip.

20. The laser diode device according to claim 19, wherein the the at least one anchoring element comprises a plurality of anchoring elements embodied as elevations and/or depressions in the underside.

21. The laser diode device according to claim 19, wherein the the at least one anchoring element comprises a first anchoring element formed by a depression or elevation in the underside and spaced from the edges of said chip and a second anchoring element formed by a stepped depression at a chip edge between the underside and the radiation coupling-out area or the rear side area or a side area.