Solid state lighting devices with improved contacts and associated methods of manufacturing

• US 8,664,684 B2
• Filed: 08/31/2010
• Issued: 03/04/2014
• Est. Priority Date: 08/31/2010
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Schubert, Martin F.
• Primary Examiner(s): YEUNG LOPEZ, FEIFEI
• Application Number:
  US12/872,092
• Publication Number:
  US 20120049756A1
• Time in Patent Office: 1,281 Days
• Field of Search: None
• US Class Current: 257/99
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 2933/0025 relating to coatings
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/14 with a carrier transport control structure, e.g. highly-doped semiconductor layer or current-blocking structure
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/36 characterised by the electrodes
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/385 the electrode extending at least partially onto a side surface of the semiconductor body
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/40 Materials therefor
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/60 Reflective elements
• 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
• CPC Class Codes: H10K 50/814 : combined with auxiliary electrodes, e.g. ITO layer combined with metal lines

Abstract

Solid state lighting (“SSL”) devices with improved contacts and associated methods of manufacturing are disclosed herein. In one embodiment, an SSL device includes an SSL structure having a first semiconductor material, a second semiconductor material spaced apart from the first semiconductor material, and an active region between the first and second semiconductor materials. The SSL device also includes a first contact on the first semiconductor material and a second contact on the second semiconductor material, where the first and second contacts define the current flow path through the SSL structure. The first or second contact is configured to provide a current density profile in the SSL structure based on a target current density profile.

Claims

1. A solid state lighting (“

SSL”

) device comprising;

a first semiconductor material;

a second semiconductor material spaced apart from the first semiconductor material;

an active region between the first and second semiconductor materials;

a contact on the first or second semiconductor material, wherein the contact includes—

a first material having a first contact resistance, wherein the first material includes an insulative material on the first semiconductor material, the insulative material having a plurality of openings extending between the first semiconductor material and a surface of the insulative material, at least one of the plurality of openings having a different shape or size from the other openings; and

a second material having a second contact resistance different than the first contact resistance, wherein the second material includes a conductive material on the insulative material, the conductive material having a first portion on the surface of the insulative material and a second portion in the openings of the insulative material; and

wherein at least one of a shape, a size, a profile, and a distribution of the first and second materials varies from one region of the SSL device to another region of the SSL device.

4. The SSL device of claim 1 wherein:

the first material includes the insulative material on the first semiconductor material,

wherein the insulative material includes—

a first region including a first number of openings; and

a second region spaced apart from the first region, wherein the second region includes a second number of openings different than the first number of openings.

2. An SSL device comprising:

a first semiconductor material;

a second semiconductor material spaced apart from the first semiconductor material;

an active region between the first and second semiconductor materials;

a first contact on the first semiconductor material;

a second contact on the second semiconductor material wherein the second contact is laterally spaced apart from the first contact;

wherein the first contact includes a first material having a first contact resistance and a second material having a second contact resistance, the first contact resistance being different from the second contact resistance;

wherein at least one of a shape, a size, a profile, and a distribution of the first and second materials varies from one region of the SSL device to another region of the SSL device;

the first material includes an insulative material on the first semiconductor material, the insulative material having a plurality of openings extending between the first semiconductor material and a surface of the insulative material, at least one of the plurality of openings having a different shape or size from the other openings; and

the second material includes a conductive material on the insulative material, the conductive material having a first portion on the surface of the insulative material and a second portion in the openings of the insulative material.

3. An SSL device comprising:

a first semiconductor material;

a second semiconductor material spaced apart from the first semiconductor material;

an active region between the first and second semiconductor materials;

a first contact on the first semiconductor material;

a second contact on the second semiconductor material wherein the second contact is laterally spaced apart from the first contact;

wherein the first contact includes a first material having a first contact resistance and a second material having a second contact resistance, the first contact resistance being different from the second contact resistance;

wherein at least one of a shape, a size, a profile, and a distribution of the first and second materials varies from one region of the SSL device to another region of the SSL device;

the first material includes an insulative material on the first semiconductor material, the insulative material having a plurality of openings extending between the first semiconductor material and a surface of the insulative material, at least one of the plurality of openings having a different shape or size from the other openings;

the second material includes a conductive material on the insulative material, the conductive material having a first portion on the surface of the insulative material and a second portion in the openings of the insulative material;

wherein the insulative material includes—

a first region including a first number of openings; and

a second region spaced apart from the first region, wherein the second region includes a second number of openings different than the first number of openings.