Effects of Finger Width & Finger Spacing on the Electrical Performance of W/CDS Based MSM Photodetector

Abstract

The metal-semiconductor-metal (MSM) alignment one of the favourable, having the benefit for its simple structure and high detection bandwidths be reach up to gigahertz ranges, constructing them appropriate for very fast on-chip optical connects, and optical communication systems. The detector property parameters like quantum efficiency and response time, stand closely associated to the bounds of electrode geometry plus optical immersion layer, wideness, etc. However, the effect of the device structure on its performance is rarely studied, which limits the development of MSM detectors. MSM structure based Tungsten/Cadmium Sulphide (W/CdS) photo detector (MSM PD) is proposed by using ATLAS Silvaco. The current-voltage (I-V) characteristics of W/CdS photodetector were investigated at different finger widths and finger spacing as well as for different epitaxial layer concentration and thickness of the epitaxial layer. All the simulation has done by illuminating a beam of light of wavelength 8 µm where peak responsivity we found as 2.96A/W.