Optoelectronic semiconductor chip and method for producing an optoelectronic semiconductor chip

• US 8,900,888 B2
• Filed: 04/08/2010
• Issued: 12/02/2014
• Est. Priority Date: 05/29/2009
• Status: Active Grant

• Current Assignee: OSRAM OLED GMBH (Ams-Osram AG)
• Original Assignee: Osram Opto Semiconductors GmbH (Ams-Osram AG)
• Inventors: Gmeinwieser, Nikolaus, Hahn, Berthold
• Primary Examiner(s): Sarkar, Asok K
• Assistant Examiner(s): Anya, Igwe U
• Application Number:
  US13/318,818
• Publication Number:
  US 20120132945A1
• Time in Patent Office: 1,699 Days
• Field of Search: 257/98, 438/16
• US Class Current: 438/16
• 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 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/24 of the light emitting region, e.g. non-planar junction
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material

Abstract

An optoelectronic semiconductor chip includes a semiconductor layer sequence. The semiconductor layer sequence contains at least one active layer for generating primary radiation. In addition, the semiconductor layer sequence includes a plurality of conversion layers, the conversion layers being designed to absorb the primary radiation at least partially and to convert it into secondary radiation of a longer wavelength than the primary radiation. Furthermore the semiconductor layer sequence comprises a roughening which extends at least into the conversion layers.

Claims

1. A method of producing an optoelectronic semiconductor chip comprising:

providing a growth substrate;

growing a semiconductor layer sequence epitaxially on the growth substrate, the semiconductor layer sequence comprising at least one active layer that generates primary radiation and a plurality of conversion layers which at least in part absorb the primary radiation and convert it into secondary radiation of a longer wavelength than the primary radiation;

forming a roughened portion which extends at least into one of the conversion layers, the material of at least one conversion layer being removed in places by roughening; and

completing the semiconductor chip,

wherein a color location of radiation emitted by the semiconductor chip is altered by the roughening,

wherein the roughened portion is of a random structure,

the semiconductor layer sequence is formed by a single layer sequence grown as a whole and which comprises both the at least one active layer and the conversion layers which are monolithically integrated in the semiconductor layer sequence, and

the semiconductor layer sequence emits radiation at least temporarily during creation of the roughened portion and the color location of the radiation emitted by the semiconductor layer sequence is measured at least temporarily.

2. The method according to claim 1, wherein a sum of a c_x value and a c_y value of the color location of the radiation emitted by the semiconductor chip is reduced in a CIE standard chromaticity diagram by at least 0.05 units during roughening.

3. The method according to claim 1, wherein the growth substrate is removed from the semiconductor layer sequence before roughening, the semiconductor chip is electrically contacted before the roughening, and the semiconductor chip is electrically operated periodically during roughening.