High-reflectivity Pd/Ni/Al/Ti/Au ohmic contacts to p-type GaN for ultraviolet light-emitting diodes

Chen, Guan-Ting; Pan, Chang-Chi; Fang, Chi-Shin; Huang, Tzu-Chien; Chyi, Jen-Inn; Chang, Mao-Nan; Huang, Sheng-Bang; Hsu, Jung-Tsung
October 2004
Applied Physics Letters;10/4/2004, Vol. 85 Issue 14, p2797
Academic Journal
Thermal stability, optical reflectivity, and contact resistivity of Pd/Ni/Al/Ti/Au ohmic contacts to p-type GaN were investigated. In contrast to its Pd/Al/Ti/Au counterparts, Pd/Ni/Al/Ti/Au contacts retained their specific contact resistivity (<2×10-2 Ω cm2) and reflectivity (>76%) after long-term annealing at 150 °C in nitrogen ambient. According to the results of the secondary ion mass spectroscopy study, it is suggested that the Ni layer prevents the penetration of Ti into GaN during thermal treatment.


Related Articles

  • High transparency of Ag/Zn–Ni solid–solution ohmic contacts for GaN-based ultraviolet light-emitting diodes. Leem, Dong-Seok; Song, June-O; Hong, Woong-Ki; Maeng, Jeong-Tae; Kwak, J. S.; Park, Y.; Seong, Tae-Yeon // Applied Physics Letters;3/7/2005, Vol. 86 Issue 10, p102102 

    Ag/Zn–Ni solid–solution scheme has been investigated to produce transparent ohmic contacts for ultraviolet (UV) light-emitting diodes (LEDs). The Ag/Zn–Ni solid–solution contacts annealed at 430 °C for 1 min in air show high transmittance of 67%–69% at 340...

  • Investigation of Cr- and Al-based metals for the reflector and Ohmic contact on n-GaN in GaN flip-chip light-emitting diodes. Kuang-Po Hsueh; Kuo-Chun Chiang; Yue-Ming Hsin; Wang, Charles J. // Applied Physics Letters;11/6/2006, Vol. 89 Issue 19, p191122 

    This letter investigates three composite metals used as a reflector and Ohmic contact on n-GaN to simplify the process in a flip-chip light-emitting diode (FCLED). The investigated composite metals were Ti/Al/Ti/Au, Cr/Al/Cr/Au, and Cr/Ti/Au. The specific contact resistivities of the...

  • Improved long-term thermal stability of InGaN/GaN multiple quantum well light-emitting diodes using TiB2- and Ir-based p-Ohmic contacts. Stafford, L.; Voss, L. F.; Pearton, S. J.; Wang, H. T.; Ren, F. // Applied Physics Letters;6/11/2007, Vol. 90 Issue 24, p242103 

    InGaN/GaN multiple quantum well light-emitting diodes (MQW-LEDs) were fabricated with either Ni/Au/TiB2/Ti/Au or Ni/Au/Ir/Au p-Ohmic contacts and annealed at 200 and 350 °C for 45 days. By comparison with companion devices with conventional Ni/Au Ohmic contacts fabricated on the same wafer,...

  • Low resistance as-deposited Cr/Au contacts on p-type GaN. Kalaitzakis, F. G.; Pelekanos, N. T.; Prystawko, P.; Leszczynski, M.; Konstantinidis, G. // Applied Physics Letters;12/24/2007, Vol. 91 Issue 26, p261103 

    The influence of several predeposition surface treatments and different contact metals to the electrical properties of metal/p-GaN contacts was studied. A low resistance as-deposited Cr/Au Ohmic contact was achieved, using boiling aqua regia as surface treatment. The Ohmic resistance of Cr/Au...

  • Low specific contact resistance Ti/Au contacts on ZnO. Chen, J.-J.; Soohwan Jang; Anderson, T. J.; Ren, F.; Yuanjie Li; Hyun-Sik Kim; Gila, B. P.; Norton, D. P.; Pearton, S. J. // Applied Physics Letters;3/20/2006, Vol. 88 Issue 12, p122107 

    Ti/Au Ohmic contacts on heavily Al-doped (n∼1019 cm-3) n-ZnO produce low specific contact resistivity of 2.4×10-7 Ω cm2 in the as-deposited condition and extremely low minimum values of 6×10-8 Ω cm2 after annealing at 300 °C.The contact resistance is independent of...

  • Efficiency degradation behaviors of current/thermal co-stressed GaN-based blue light emitting diodes with vertical-structure. Liu, Lilin; Ling, Minjie; Yang, Jianfu; Xiong, Wang; Jia, Weiqing; Wang, Gang // Journal of Applied Physics;May2012, Vol. 111 Issue 9, p093110 

    With this work, we demonstrate a three-stage degradation behavior of GaN based LED chips under current/thermal co-stressing. The three stages in sequence are the initial improvement stage, the platform stage, and the rapid degradation stage, indicating that current/thermal co-stressing activates...

  • Electroless nickel/gold Ohmic contacts to p-type GaN. Lewis, L.; Casey, D. P.; Jeyaseelan, A. V.; Rohan, J. F.; Maaskant, P. P. // Applied Physics Letters;2/11/2008, Vol. 92 Issue 6, p062113 

    A solution based approach to forming Ohmic contacts to p-type GaN is described. Electroless plated Ni/Au contacts are shown to compare favorably with traditional evaporated contacts, with contact resistivities ρc in the region of 10-2 Ω cm2. These values are readily achieved after a rapid...

  • Efficient, single-layer molecular organic light-emitting diodes. Lane, Paul A.; Kushto, Gary P.; Kafafi, Zakya H. // Applied Physics Letters;1/8/2007, Vol. 90 Issue 2, p023511 

    The authors demonstrate efficient molecular organic light-emitting diodes that use direct hole injection from poly(3,4-ethylene-dioxythio-phene):poly(styrene-sulfonate) into a single layer of tris(8-hydroxyquinoline) aluminum (III) for carrier transport and electroluminescence. Single-layer...

  • Effect of Cl2/Ar dry etching on p-GaN with Ni/Au metallization characterization. Kuang-Po Hsueh; Hung-Tsao Hsu; Che-Ming Wang; Shou-Chian Huang; Yue-Ming Hsin; Jinn-Kong Sheu // Applied Physics Letters;12/19/2005, Vol. 87 Issue 25, p252107 

    This work investigates the effect of Cl2/Ar dry etching on p-GaN. The root-mean-square (rms) surface roughness is measured, and the depth display (Bearing analysis) is monitored. The current-voltage characteristics of etched p-GaN with Ni (20 nm)/Au (20 nm) metallization are studied....


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics