Analysis of electrical and optical characteristics of InGaSb PIN photodiodes

This study represents an analysis of electrical and optical characteristics of InGaSb PIN photodiodes. The electrical characteristics are analysed by depicting a model of zero-bias resistance-area product (R₀A) of such photodiodes. The effects of dislocation and temperature on R₀A are also included in the model. Different optoelectronic properties of the material are extracted by fitting the obtained models with experimental data. The extracted dislocation density is 6.67×10⁸ cm^-2, which is close to the measured value of 2.4(±0.2)±10⁸ cm^-2. Through the dislocation and temperature-dependent modelling, maximum R₀A is found to be 1.85 Ω cm² at 139 K. Experimental data obtained at 300 and 363 K are fitted with theoretical model. The optical properties are analysed by the modelling of responsivity, quantum efficiency and detectivity. Cutoff wavelength is found to be 2271 nm, which is within 5 nm of the experimentally obtained data. The present analysis gives a photodiode responsivity is 0.47 A/W, quantum efficiency is 28.86 and detectivity is 1.53 10⁹ cm Hz^1/2/W¹ at a particular wavelength of λ=2.0 μm, which are agreeable to the experimentally obtained data.