This relationship can explain the increment of barrier height in the printed SBDs. In the Ag/p-Si interface, the charge transfer occurs from the AgNPs attached on the Ag electrode surface to p-Si developing partial positive charges at the Ag electrode surface. The formed depletion layer spreads and becomes thicker in the depth, because electron mobility is limited in the printed Ag electrodes due to cracks and boundary defects in the electrodes. Increased thickness of depletion layer (W) can then increase the apparent barrier height (B) as predicted based on the equation ( ), though the existence of AgNPs at the interface leads to the increase in the work function (up to 0.25 eV as compared to that of an vacuum-deposited Ag electrode).