Siti Kudnie Sahari1, Ibrahim Ahmad2, Asban Dolah2


1Department of Electronics and Computer,

Faculty of Engineering, Universiti Malaysia Sarawak,

94300 Kota Samarahan,

Sarawak, Malaysia,

2Institute of Micro and Nano Engineering (IMEN)

43600 UKM Bangi, Selangor, Malaysia,


Email: sskudnie@feng.unimas.my





Ohmic contact of Ge/ Au/ Ni to AlGaAs substrate was studied by varying treatment of the samples with hydrochloric acid and ammonium hydroxide. The samples were etched by wet chemical solutions to determine the most effective solution to remove native oxide that degrades the performance of the devices. The annealing temperature and the length of time were varied to determine the lowest contact resistance. Transmission Line Measurement was used to measure the contact resistance. Result shows that the anneal time at temperature 400 C for 60 seconds yields the best ohmic contact. The most effective wet solution that can remove native oxide is hydrochloric acids.





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