An analysis for design optimization of mesh-type high-speed optical position sensitive devices (MEPSDs)

摘要

An analysis is given for designing high-speed optical position-sensitive devices (PSDs) with mesh-type resistive layers used for reducing the junction capacitance. For the MEPSD, reduction of the capacitance is dependent on the selection of the strip width and strip distance, and they should be selected in such a way that the diffusion time of the carriers must not dominate the response time, compared with the RC time constant of the devices. This analysis includes the effect of the surface recombination velocity on the collected current, and it can be applied to the choice of the optimal parameters for designing the MEPSD. From the results it is found that MEPSD of 5*5 cm/sup 2/ can be designed to operate two orders of magnitude faster than the conventional-type PSD.