Forward I-V characteristics of a series of printed SBDs represented in Figure were used to extract Schottky parameters in order to investigate the effect of the sintering time. Among some methods proposed to deduce the Schottky parameters from forward I-V characteristics, we used the method by Cheung et al. because of high applicable for our results. The forward I-V characteristics of the diode obeying the thermionic emission model are given by equation ( ), (1) where Aeff, A*, T, qB, n, and rs are effective area of the diode, Richardson constant, absolute temperature, Schottky barrier height, ideality factor, and series resistance, respectively. The constant value of  is 38.9 C•J -1 at the room temperature (T = 298 K) where q and k are electronic charge and Boltzmann constant, respectively. The Richardson constant, A* is 32 A• cm -2 •K -2 for p-Si. The ideality factor, n is included to take into account non ideal diode behaviors, where n is equal to 1 for the ideal diode. Generally, n becomes more than 1 for the real device because n varies mainly depending on physical processes for carrier transport across the M/S interface of the diode. The equation ( ) is derived to equation (2) in the case of V-I•rs > 3kT/q (∼0.08 V at 298 K).