Spectral Sensitivity of Graphene/Silicon Heterojunction Photodetectors

TL;DR

This study investigates the optical properties and spectral sensitivity of graphene/silicon heterojunction photodetectors, revealing superior rectification and responsivity on n-type silicon substrates and comparing their performance with MoS2-based devices.

Contribution

It provides new insights into the spectral sensitivity and rectification behavior of graphene/silicon heterojunction photodetectors, especially on n-type silicon, and compares their performance with MoS2-based photodiodes.

Findings

Better rectification on n-type silicon substrates.

Responsivity of 270 mA/W in silicon spectral range.

Comparison with MoS2/p-type silicon photodiodes.

Abstract

We have studied the optical properties of two-dimensional (2D) Schottky photodiode heterojunctions made of chemical vapor deposited (CVD) graphene on n- and p-type Silicon (Si) substrates. Much better rectification behavior is observed from the diodes fabricated on n- Si substrates in comparison with the devices on p-Si substrates in dark condition. Also, graphene/n-Si photodiodes show a considerable responsivity of 270 mA/W within the silicon spectral range in DC reverse bias condition. The present results are furthermore compared with that of a molybdenum disulfide (MoS2)/p-type silicon photodiodes.