Electrical behaviour of metal/tetrahedral amorphous carbon/metal structure

Silicon and GaAs based devices are limited in their high-temperature applications as these materials lack high sensitivity to the temperature range above 200°C due to their small band gaps. Therefore, exploration of new materials with a high-temperature performance is necessary. Diamond-like carbon as a semiconducting material may be one of the promising candidates due to its many properties close to those of diamond. The main objective of this study is to investigate tetrahedral amorphous carbon (ta-C) film based metal-semiconductor-metal (MSM) structures targeted at high-temperature applications. The ta-C films were deposited in a filtered cathodic vacuum arc (FCVA) process. For the deposition of nitrogen-doped n-type ta-C films, N⁺ ion beam was used to assist the doping process during deposition. Several metals of high purity, such as Cr, Ti, etc., were selected for this purpose. The high-temperature performance of MSM structures was evaluated by measuring their I-V characteristics at different temperatures up to 300°C. Al/n-ta-C/Al structure likely shows clear Schottky behaviour among the selected metals, while Ti/n-ta-C/Ti and Cr/n-ta-C/Cr show typical ohmic contact behaviour in the testing temperature range.