S. P. Wang, Y. C Lin, Y. L. Tseng, K. S. Chen, J. C. Huang and E. Y. Chang
Department of Materials Science and Engineering, National Chiao-Tung University, Hsinchu 30010, Taiwan, R.O.C., E-mail: email@example.com, Phone number: +886-35712121 EXT: 31536
Keywords: Cu, InGaP, HBT, ohmic contact, power
The Cu-metalized InGaP/GaAs HBTs using Pd/Ge/Cu ohmic contact to n-type GaAs, Pt/Ti/Pt ohmic contact to p+-type GaAs, and Ti/Pt/Cu for interconnect metals with Pt as the diffusion barrier has been successfully fabricated for power application. The Pd/Ge/Cu metal structure forms a low contact resistance ohmic contact to n-type GaAs with a low specific contact resistivity of 5.73 x 10-7 Ω-cm2 after annealed at 250 °C for 20 minutes. The 4 x 20μm2 Cu-metalized InGaP/GaAs HBTs demonstrated a power of 10.06dBm with power efficiency of 35.6%.