Temperature dependence of the optical gap of diamond-like carbon films investigated by a piezoelectric photothermal spectroscopy

Wen Ding, Yosuke Nakano, Ryoichi Yamamoto, Kentaro Sakai, Hideki Nakazawa, Atsuhiko Fukuyama, Tetsuo Ikari
2011 Energy Procedia  
Temperature dependences of the optical gap of diamond-like carbon (DLC) films were investigated by using a piezoelectric photothermal (PPT) spectroscopy, that detects the nonradiative transition of photoexcited electrons. Since the PPT signal intensity is expected to be proportional to its optical absorption coefficient, the optical gap was estimated by a Tauc plot. The temperature coefficient of the optical gap energy was found to be very small compared with that of other semiconductor such as
more » ... Si. This result implies that the device performance is expected to be stable by temperature change and the DLC films are excellent as the next generation solar cells materials.
doi:10.1016/j.egypro.2011.10.154 fatcat:25pzouxwbnaerpcexx2ycb5hge