Vertical solid-state transducers having backside terminals and associated systems and methods

• US 9,196,810 B2
• Filed: 04/16/2013
• Issued: 11/24/2015
• Est. Priority Date: 08/25/2011
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Odnoblyudov, Vladimir, Schubert, Martin F.
• Primary Examiner(s): PARENDO, KEVIN A
• Application Number:
  US13/863,625
• Publication Number:
  US 20130228815A1
• Time in Patent Office: 952 Days
• Field of Search: 438/98, 257/459
• US Class Current: 1/1
• 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 2933/0033 relating to semiconductor body packages
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/0058 relating to optical field-shaping elements
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through 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 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/501 characterised by the materials, e.g. binder
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/58 Optical field-shaping 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: H01L 33/647 the elements conducting electric current to or from the semiconductor body

Abstract

Vertical solid-state transducers (“SSTs”) having backside contacts are disclosed herein. An SST in accordance with a particular embodiment can include a transducer structure having a first semiconductor material at a first side of the SST, a second semiconductor material at a second side of the SST opposite the first side, and an active region between the first and second semiconductor materials. The SST can further include first and second contacts electrically coupled to the first and second semiconductor materials, respectively. A portion of the first contact can be covered by a dielectric material, and a portion can remain exposed through the dielectric material. A conductive carrier substrate can be disposed on the dielectric material. An isolating via can extend through the conductive carrier substrate to the dielectric material and surround the exposed portion of the first contact to define first and second terminals electrically accessible from the first side.

Claims

1. A solid-state transducer (SST) having a first side and a second side facing away from the first side, comprising:

a transducer structure having a first semiconductor material at the first side of the SST, a second semiconductor material at the second side of the SST, and an active region between the first and second semiconductor materials;

a first contact on the first side of the SST and electrically coupled to the first semiconductor material, wherein the first contact includes an isolated portion covered by a dielectric material and an exposed portion not covered by the dielectric material;

a second contact on the first side of the SST and electrically coupled to the second semiconductor material, the second contact comprising—

a plurality of interconnected buried contact elements that extend from the first side of the SST into the second semiconductor material, wherein the buried contact elements are electrically isolated from the active region, the first semiconductor material, and the first contact;

a plurality of conductive lines on the dielectric material and interconnecting the buried contact elements,

wherein the second contact includes an isolated portion covered by dielectric portions and an exposed portion not covered by the dielectric portions; and

a conductive carrier substrate over the dielectric material on first side of the SST, wherein the conductive carrier substrate defines a first terminal electrically coupled to the first contact and a second terminal electrically coupled to the second contact;

an isolating via extending through the conductive carrier substrate to the dielectric material, the isolating via surrounding the exposed portion of the first contact;

a plurality of separators extending from the first side of the SST beyond the second semiconductor material to form a plurality of protrusions, wherein the separators define individual SST dies; and

a conductive material on the dielectric portions, the dielectric material, and the exposed portions of the first and second contacts, wherein the conductive material contacts the exposed portions, and wherein the conductive carrier substrate is configured to be formed on the conductive material.

2. The SST of claim 1 wherein the separators comprise a dielectric isolator adjacent to the transducer structure.

3. The SST of claim 1 wherein the separators are aligned with dicing lanes.

4. The SST of claim 1 wherein the protrusions are on the second side of the SST around a periphery of the individual SST dies, and wherein an optical element is confined within the protrusion.

5. The SST of claim 1 wherein the individual SST dies are configured to emit electromagnetic radiation in at least one of the ultraviolet spectrum, the visible spectrum, and the infrared spectrum.

6. A solid-state transducer (SST) having a first side and a second side facing away from the first side, comprising:

a transducer structure having a first semiconductor material at the first side of the SST, a second semiconductor material at the second side of the SST, and an active region between the first and second semiconductor materials;

a first contact on the first side of the SST and electrically coupled to the first semiconductor material, wherein the first contact includes an isolated portion covered by a dielectric material and an exposed portion not covered by the dielectric material;

a second contact on the first side of the SST and electrically coupled to the second semiconductor material, the second contact comprising a plurality of interconnected buried contact elements;

a conductive carrier substrate over the dielectric material on first side of the SST, wherein the conductive carrier substrate defines a first terminal electrically coupled to the first contact and a second terminal electrically coupled to the second contact;

a first isolating via extending through the conductive carrier substrate to the dielectric material, the first isolating via surrounding the exposed portion of the first contact and defining the first terminal at a backside of the conductive carrier substrate, the backside being on the first side of the SST;

a second isolating via extending through the conductive carrier substrate to the dielectric material, the second isolating via surrounding the exposed portion of the second contact; and

a plurality of separators extending from the first side of the SST beyond the second semiconductor material to form a plurality of protrusions, wherein the separators define individual SST dies.

7. The SST of claim 6, further comprising:

a plurality of discrete optical elements on the second side of the SST, wherein the protrusions act as barriers between the discrete optical elements.

8. The SST of claim 7 wherein the plurality of discrete optical elements comprises at least one of a plurality of discrete converter elements and a plurality of discrete cover elements, and wherein the protrusions separate the discrete converter elements and the discrete cover elements.

9. The SST of claim 7 wherein the discrete optical elements comprise:

a first converter element on a first SST die, the first converter element being configured to emit light having a first color; and

a second converter element on a second SST die adjacent to the first SST die, the second converter element being configured to emit light having a second color different from the first color.

10. A method of forming solid-state transducers (SSTs) having a first side and a second side, the method comprising:

forming a transducer structure having an active region positioned between a first semiconductor material and a second semiconductor material, wherein the first semiconductor material is at the first side of the SST and the second semiconductor material is at the second side of the SST;

forming a first contact electrically coupled to the first semiconductor material and on the first side of the SSTs;

forming a second contact electrically coupled to the second semiconductor material and on the first side of the SST, wherein the second contact includes a plurality of interconnected buried contact elements;

forming a dielectric material on the first side of the SST, wherein the first contact includes an isolated portion covered by the dielectric material and an exposed portion not covered by the dielectric material;

disposing a conductive carrier substrate on the dielectric material over the first side of the SSTs, wherein the conductive carrier substrate defines a first terminal electrically coupled to the first contact and a second terminal electrically coupled to the second contact;

forming an isolating via extending through the conductive carrier substrate to the dielectric material, the isolating via surrounding the exposed portion of the first contact; and

forming a plurality of separators extending from the first side of the SSTs beyond the second semiconductor material to form a plurality of protrusions, wherein the separators define individual SSTs, and wherein forming the plurality of separators comprises—

forming a plurality of trenches from the first side of the SST, wherein the trenches have sidewalls that extend from at least the first semiconductor material beyond the second semiconductor material into an underlying growth substrate;

depositing a dielectric isolator into the trenches; and

removing the growth substrate from the second semiconductor material and from the sidewalls such that the separators form the plurality of protrusions extending beyond the second semiconductor material.