This article presents the design and fabrication process of a two-dimensional hydrogenated amorphous silicon (a-Si:H) n-i-p photodiode array, developed for low, light level sensor applications. Utilization of the single a-Si:H switching diode for signal readout enables simpler device design and fabrication. Since the sensing and switching diodes are formed simultaneously by dry etching the a-Si:H layers deposited over the whole area, the number of masks required in lithography was reduced to six. A significant reduction of the leakage current has been achieved by tailoring defects at the i-p interface and optimizing the plasma processing conditions. Details of device fabrication along with results of the sensor array performance are presented. (C) 2004 American Vacuum Society.