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Title: LED structure with enhanced mirror reflectivity

Abstract

Embodiments of the present invention are generally related to LED chips having improved overall emission by reducing the light-absorbing effects of barrier layers adjacent mirror contacts. In one embodiment, a LED chip comprises one or more LEDs, with each LED having an active region, a first contact under the active region having a highly reflective mirror, and a barrier layer adjacent the mirror. The barrier layer is smaller than the mirror such that it does not extend beyond the periphery of the mirror. In another possible embodiment, an insulator is further provided, with the insulator adjacent the barrier layer and adjacent portions of the mirror not contacted by the active region or by the barrier layer. In yet another embodiment, a second contact is provided on the active region. In a further embodiment, the barrier layer is smaller than the mirror such that the periphery of the mirror is at least 40% free of the barrier layer, and the second contact is below the first contact and accessible from the bottom of the chip.

Inventors:
; ; ; ; ;
Issue Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1128704
Patent Number(s):
8686429
Application Number:
13/168,689
Assignee:
Cree, Inc. (Durham, NC)
Patent Classifications (CPCs):
H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01L - SEMICONDUCTOR DEVICES
DOE Contract Number:  
EE0000641
Resource Type:
Patent
Resource Relation:
Patent File Date: 2011 Jun 24
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING

Citation Formats

Bergmann, Michael, Donofrio, Matthew, Heikman, Sten, Schneider, Kevin S, Haberern, Kevin W, and Edmond, John A. LED structure with enhanced mirror reflectivity. United States: N. p., 2014. Web.
Bergmann, Michael, Donofrio, Matthew, Heikman, Sten, Schneider, Kevin S, Haberern, Kevin W, & Edmond, John A. LED structure with enhanced mirror reflectivity. United States.
Bergmann, Michael, Donofrio, Matthew, Heikman, Sten, Schneider, Kevin S, Haberern, Kevin W, and Edmond, John A. Tue . "LED structure with enhanced mirror reflectivity". United States. https://www.osti.gov/servlets/purl/1128704.
@article{osti_1128704,
title = {LED structure with enhanced mirror reflectivity},
author = {Bergmann, Michael and Donofrio, Matthew and Heikman, Sten and Schneider, Kevin S and Haberern, Kevin W and Edmond, John A},
abstractNote = {Embodiments of the present invention are generally related to LED chips having improved overall emission by reducing the light-absorbing effects of barrier layers adjacent mirror contacts. In one embodiment, a LED chip comprises one or more LEDs, with each LED having an active region, a first contact under the active region having a highly reflective mirror, and a barrier layer adjacent the mirror. The barrier layer is smaller than the mirror such that it does not extend beyond the periphery of the mirror. In another possible embodiment, an insulator is further provided, with the insulator adjacent the barrier layer and adjacent portions of the mirror not contacted by the active region or by the barrier layer. In yet another embodiment, a second contact is provided on the active region. In a further embodiment, the barrier layer is smaller than the mirror such that the periphery of the mirror is at least 40% free of the barrier layer, and the second contact is below the first contact and accessible from the bottom of the chip.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2014},
month = {4}
}

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    Works referencing / citing this record:

    High voltage monolithic LED chip
    patent, August 2017


    Hybrid reflector system for lighting device
    patent, September 2016


    Graded vias for LED chip P- and N- contacts
    patent, August 2016


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    patent, June 2016