| Popis: |
In this paper, the influences of thermal and spectral variations on various structures of avalanche photodiodes (APDs) have been deeply investigated. The characteristics and performance of Silicon (Si), Gallium Arsenide (GaAs) and Indium Gallium Arsenide (InGaAs) avalanche photodiodes have been evaluated under effects of different temperature degrees. The impacts of different temperature levels on the band gap energy, detector responsivity, noise equivalent power (NEP), cut-off wavelength, dark current and the photocurrent are studied and analyzed in details. The signal to noise ratio (SNR) and Bit Error Rate (BER) of these APDs are also computed and measured under the influences of different temperature levels and spectral variations. The aim of this paper is to determine the most efficient avalanche photodiode achieving the best performance according to the maximum SNR and minimum BER at high temperature environments. The analysis of the proposed model is performed by MATLAB. It was found that the experimental measured results endorse the analytical computed results. Further, it was observed that the APD (InGaAs) provides performance better than other APD structures in terms of larger SNR and less BER at higher temperature levels. Also, the temperature has a slight effect on the performance of APD (GaAs). So, it is seemed to be stable more than other APD structures and recommended to be used in warm environments and for high temperature applications. Keywords: Thermal effects, NEP, Dark current, Noise current, Photocurrent, SNR and BER |
