In this study, we investigated electrical properties of amorphous carbon (a-C : H) films fabricated by plasma CVD. First, photovoltaic cells consisting of Au/ a-C : H films / n-Si (p-Si) /In-Ga films were fabricated with changing deposition condition. Deposition of a-C"H films were performed using methane as a source gas. Nitrogen and tri-methyl boron (TMB) were also used as the doping gases. Under the light illumination (Xe are lamp at 100mW/cm^2), this cell shows photovoltaic behavior with short circuit current of 0.3mA/cm^2,open circuit voltage of 0.3V and energy conversion efficiency of 0.023%. Secondly, we investigated field emission from a-C : H on ITO films. The film shows field emission at the surface potential barrier of 4∿4.5eV.