Compensation for RC-effects in organic photodiodes with large sheet resistances

Transient measurements on semiconductor devices are distorted by parasitic effects due to the geometric capacitance of the device and the impedance of the attached measurement circuit. Together they form an RC-circuit. Ideally, the transient decay of the pulse response generated by such an RC-circuit follows an exponential function. We investigate the differential equations of the case of an oblong rectangular photodiode with significant sheet resistance of one electrode. We find that under a specific illumination profile the ideal RC-decay can be obtained which is an useful result for RC-compensation in organic photodiodes.