JSTS:Journal of Semiconductor Technology and Science

The Institute of Electronics and Information Engineers (대한전자공학회)
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Reduction of Current Crowding in InGaN-based Blue Light-Emitting Diodes by Modifying Metal Contact Geometry

  • Kim, Garam (Inter-University Semiconductor Research Center and Department of Electrical Engineering, Seoul National University) ;
  • Kim, Jang Hyun (Inter-University Semiconductor Research Center and Department of Electrical Engineering, Seoul National University) ;
  • Park, Euyhwan (Inter-University Semiconductor Research Center and Department of Electrical Engineering, Seoul National University) ;
  • Park, Byung-Gook (Inter-University Semiconductor Research Center and Department of Electrical Engineering, Seoul National University)
  • Received : 2014.05.12
  • Accepted : 2014.07.30
  • Published : 2014.10.30
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Abstract

Current crowding problem can worsen the internal quantum efficiency and the negative-voltage ESD of InGaN-based LEDs. In this paper, by using photon emission microscope and thermal emission microscope measurement, we confirmed that the electric field and the current of the InGaN-based LED sample are crowded in specific regions where the distance between p-type metal contact and n-type metal contact is shorter than other regions. To improve this crowding problem of electric field and current, modified metal contact geometry having uniform distance between the two contacts is proposed and verified by a numerical simulation. It is confirmed that the proposed structure shows better current spreading, resulting in higher internal quantum efficiency and reduced reverse leakage current.

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References

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