Metal contacts to p-type GaN by electroless deposition

Casey, Declan P.; Lewis, Liam; Rohan, James F.; Maaskant, Pleun P.

Metal contacts to p-type GaN by electroless deposition

Files

9690.pdf(850.58 KB)

Accepted version

Date

2007-09

Authors

Casey, Declan P.

Lewis, Liam

Rohan, James F.

Maaskant, Pleun P.

Publisher

Society of Photo-optical Instrumentation Engineers (SPIE)

Published Version

10.1117/12.758947

Abstract

Initial results are presented on the electroless deposition of metal contacts to p-type gallium nitride (GaN). Deposition procedures were developed for the deposition of both nickel and tungsten-cobalt (W-Co) contacts onto p-type GaN. Attempts to deposit platinum on p-type GaN failed, despite the fact that electroless platinum deposition was successfully achieved on other substrate types. Nickel contacts were overlaid with gold and annealed in oxygen ambient to form ohmic contacts with specific contact resistivity values down to 2x10-2 &OHgr;cm2. Measurements at elevated temperatures up to 140 degrees C showed that the specific contact resistivity was almost independent of temperature. The tungsten-cobalt contacts showed rectifying behaviour even after annealing at 650 degrees C. This makes this contact type a possible candidate for Schottky contacts in high temperature applications.

Keywords

p-type GaN , Ohmic contact , Electroless deposition

Citation

Lewis, L., Casey, D., Rohan, J. F. and Maaskant, P. P. (2007) ‘Metal contacts to p-type GaN by electroless deposition', Proceedings of SPIE, 6797, Manufacturing LEDs for Lighting and Displays; Berlin, Germany, 10-11 September, 67970J, doi: 10.1117/12.758947