Spectral Response of Al/Si Photodiode as IR Sensor

TL;DR

This paper investigates the spectral response of Al/Si photodiodes, demonstrating their sensitivity to IR wavelengths from 800 to 1000 nm, with a peak at 981 nm, and analyzing their quantum efficiency and sensitivity.

Contribution

It presents a novel fabrication method for Al/Si photodiodes and characterizes their spectral response and sensitivity in the IR range.

Findings

Sensitivity peaks at 981 nm wavelength.

Quantum efficiency of 6.16% observed.

Current sensitivity measured at 0.488 nA/μW/cm².

Abstract

Al/Si photodiode were prepared by successive of deposition of Aluminum thin films on p-type Si (100) using coprecipitation method by evaporator in vacuum 2.0E-4 torr. The measured signals are attributed to a spectral response, which appears in the studied photodiode. The photodiode Al/Si is sensitivity over a broad range of IR wavelengths from 800 to 1000 nm, when illuminated with discontinuous light at chopper frequency 200 Hz. The spectral response distribution that sensitivity peaks appear when the measurement was performed using the ac mode. The peak was at 981 nm, the incident radiation power (Pi) at the surface was 25 microwatt/cm2, the current signal (Ip) was 12.2 nA, the quantum efficiency was 6.16 % and the current sensitivity was 0.488 nA/microwatt/cm2.