Electrical behaviour of metal/tetrahedral amorphous carbon/metal structure

Silicon and GaAs based devices are limited in their high-temperature applic ations as these materials lack high sensitivity to the temperature range ab ove 200 degrees C due to their small band gaps. Therefore, exploration of n ew 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 o f this study is to investigate tetrahedral amorphous carbon (ta-C) film bas ed metal-semiconductor-metal (MSM) structures targeted at high-temperature applications. The ta-C films were deposited in a filtered cathodic vacuum a re (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. Severa l metals of high purity, such as Cr, Ti, etc., were selected for this purpo se. The high-temperature performance of MSM structures was evaluated by mea suring their I-V characteristics at different temperatures up to 300 degree s 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 co ntact behaviour in the testing temperature range. (C) 1998 Elsevier Science Ltd. All rights reserved.