# Photo-Piezojunction Coupling Effect in n-3C-SiC/p-Si Heterojunction – A Platform for Self-Powered Strain-Sensing Applications

## TL;DR

This paper introduces a self-powered strain sensor using a silicon carbide-silicon junction that combines light and pressure sensing for smart infrastructure applications.

## Contribution

The paper introduces the novel photo-piezojunction coupling effect in n-3C-SiC/p-Si heterojunctions for self-powered strain sensing.

## Key findings

- The device generates 24.54 mV with 10 μW laser power, five times higher than similar devices.
- It achieves strain sensitivity of 43.14 and 21.34 for tensile and compressive strain, 4.3 times higher than previous studies.

## Abstract

It is beneficial
to investigate multifunctional self-powered
sensors
with high sensitivity and energy-scavenging capabilities, which are
essential for the development of a smart infrastructure in the era
of 5G and Internet of Things (IoT). This paper reports the photo-piezojunction
coupling effect, i.e., the coupling of piezojunction effect with photovoltaic
effect, in an n-type 3C-SiC/p-type Si heterojunction (n-3C-SiC/p-Si)
and demonstrates it through a proof-of-concept self-powered strain-sensing
device. The device exhibits superior photon energy-harvesting capability,
generating 24.54 mV with a laser power of only 10 μW, approximately
five times higher than that of reported devices utilizing the lateral
photovoltaic effect, and an exceptionally high strain sensitivity,
achieving |(ΔV/V)/ε|
ratios of 43.14 and 21.34 for tensile and compressive strain, respectively,
which are 4.3 times more than that of devices reported in previous
studies. The findings of this study significantly advance the understanding
of the photo-piezojunction coupling effect in n-3C-SiC/p-Si heterostructures,
laying the foundation for the development of multifunctional sensor
systems capable of harvesting photon energy.