Photogenerated carrier conduction mechanisms for Schottky a‐Si:H solar cells

Carrier conduction mechanisms are described for Schottky a‐Si:H solar cells. Characteristics of a‐Si:H cells under illumination are very close to those of an ideal semiconductor whereas dark I–U characteristics indicate space charge limited phenomena. Barrier height values, relationships between metal work function and barrier height, and temperature independent carrier conduction mechanisms are observed and analyzed. Barrier height values for Pd and Cr a‐Si:H Schottky solar cells are 0.94 and 0.80 eV, respectively. The relationship φ_m = 0.23φ_B ‐ 0.25 eV is derived. U_0c decreases by about 2 mV/K with increasing temperature but is also a function of incident photon density. Diode quality factor, n₁, is 1.08 under illumination and independent of both, temperature and Schottky barrier metal.