InGaN/GaN Multiple Quantum Well Blue Light Emitting Diodes with Transparent Ni/ITO and Pt/ITO p-Type Contacts

  • Kuldip SinghEmail author
  • A. Chauhan
  • Manish Mathew
  • Rajesh Punia
  • Rajender Singh Kundu
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 215)


InGaN/GaN multiple quantum wells (MQWs) light-emitting diodes (LEDs) with Ni/ITO (5/50 nm) and Pt/ITO (0.8/50 nm) current spreading layer were investigated. The electrical and optical properties of Ni/ITO and Pt/ITO films were also investigated. It was found that the normalized transmittance of Ni/ITO and Pt/ITO films could reach 79.22 and 78.98% at 460 nm, which was almost equal. It was also found that Pt/ITO had showed better linear current–voltage characteristics compared to Ni/ITO contacts. The specific contact resistance for Pt/ITO contacts was 5.88 × 10−2 Ω cm2, while for Ni/ITO contacts, it was 5.66 × 10−1 Ω cm2 i.e. ~10 time more. The EL intensity of blue LED was much higher with Pt/ITO p-contact compared to Ni/ITO p-contact. The forward voltages (VF) of LEDs for two contacts (Ni/ITO and Pt/ITO p-contacts) at 20 mA current injection were found 4.49 and 3.5 V, respectively.



This work was supported by council of scientific and industrial research (CSIR) under network programme (PSC-0102).


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Kuldip Singh
    • 1
    Email author
  • A. Chauhan
    • 1
  • Manish Mathew
    • 1
  • Rajesh Punia
    • 2
  • Rajender Singh Kundu
    • 2
  1. 1.Optoelectronics Devices GroupCSIR-Central Electronics Engineering Research InstitutePilaniIndia
  2. 2.Department of Applied PhysicsGuru Jambheshwar University of Science and TechnologyHisarIndia

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