Effect of illumination positioning on the characteristics of an In0.53Ga0.47as interdigitated lateral PIN photodiode

The interdigitated lateral p-i-n photodiode (ILPP) based on In0.
53
Ga
0.47
As absorbing layer is an attractive alternative device to be used in optical communication networks operating at 10 Gbps or lower. Its simple fabrication methodology utilizing diffusion/ion implantation to form the p+ and n+ regions is a cost-reducing technique versus those used in developing conventional p-i-n photodiodes. A three-dimensional model of this device was developed and the device achieved dark currents of 0.21 nA, responsivity of 0.56 A/W, external quantum efficiency of 44 %, -3dB frequency of 8.93 GHz and signal-to-noise ratio, SNR of 36 dB at an operating voltage of 5 V, λ=1.55 μm and P=10 Wcm
⁻²
. Another significant advantage of the ILPP device is that it can be illuminated from three different angles; ie from the surface, from the edge and also from the bottom. In this paper, we attempt to compare the impact of optical beam illumination positioning on the common device characteristics.