C. Coçkun¹, H. Efeoğlu¹, H.S. Güder¹, B. Abay¹, Ş. Aydoğan¹, T. Karacahı², Y.K. Yoğurtçu^1
1Ataturk University, Faculty of Science and Arts, Physics Department 25240 Erzurum, Turkey
²Ataturk University, Faculty of Engineering Department of Electronics and Communication, 25240 Erzurum, Turkey

Abstract. A systematic study on ohmic contact formation to GaTe layered crystal grown by directional freezing method has been introduced. In this study the Ladder network (Transmission Line Method, TLM) technique was used for the measurement of specific contact resistance of ohmic contacts to GaTe. In, Au, Al, Ag metals and Au-In eutectic alloy were used as contact element. Ladder pattern formed directly on GaTe surface by evaporation of metals through a pre-patterned shadow mask. With a controllable thermal heat treatment process, the lowest ohmic contact with 2 .5 ± 1.4×10^-5 Ohm/cm² was formed by In after annealing at 200℃ for 2 .5 min. Ohmic contacts with that process remained very stable up to six months although the other samples with higher contact resistance processed at l 75–250℃ for 2.5–14 min were unstable. X-ray diffraction measurements showed that GaInTe₂ formation at In-GaTe interface even prior to annealing process. The other elements used in this study showed rectification behaviour after annealing at 175–400℃ temperature range for 5 min.

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