Nguyen Thanh, Dinh Toan, Dau Van Thanh, Md Foisal Abu Riduan, Guzman Pablo, Nguyen Hung, Pham Tuan Anh, Nguyen Tuan-Khoa, Phan Hoang-Phuong, Nguyen Nam-Trung, Dao Dzung Viet
Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, QLD 4111, Australia.
Centre for Future Materials, University of Southern Queensland, Toowoomba, QLD 4350, Australia.
ACS Appl Mater Interfaces. 2021 Jul 28;13(29):35046-35053. doi: 10.1021/acsami.1c05985. Epub 2021 Jul 8.
Giant piezoresistive effect enables the development of ultrasensitive sensing devices to address the increasing demands from hi-tech applications such as space exploration and self-driving cars. The discovery of the giant piezoresistive effect by optoelectronic coupling leads to a new strategy for enhancing the sensitivity of mechanical sensors, particularly with light from light-emitting diodes (LEDs). This paper reports on the piezoresistive effect in a 3C-SiC/Si heterostructure with a bonded LED that can reach a gauge factor (GF) as high as 18 000. This value represents an approximately 1000 times improvement compared to the configuration without a bonded LED. This GF is one of the highest GFs reported to date for the piezoresistive effect in semiconductors. The generation of carrier concentration gradient in the top thin 3C-SiC film under illumination from the LED coupling with the tuning current contributes to the modulation of the piezoresistive effect in a 3C-SiC/Si heterojunction. In addition, the feasibility of using different types of LEDs as the tools for modulating the piezoresistive effect is investigated by evaluating lateral photovoltage and photocurrent under LED's illumination. The generated lateral photovoltage and photocurrent are as high as 14 mV and 47.2 μA, respectively. Recent technologies for direct bonding of micro-LEDs on a Si-based device and the discovery reported here may have a significant impact on mechanical sensors.
巨压阻效应推动了超灵敏传感设备的发展，以满足太空探索和自动驾驶汽车等高技术应用日益增长的需求。通过光电耦合发现的巨压阻效应为提高机械传感器的灵敏度带来了新策略，特别是利用发光二极管（LED）发出的光。本文报道了一种带有键合LED的3C-SiC/Si异质结构中的压阻效应，其应变片系数（GF）高达18000。与没有键合LED的结构相比，该值提高了约1000倍。这个GF是迄今为止报道的半导体压阻效应中最高的GF之一。在LED耦合调谐电流的光照下，顶部薄3C-SiC薄膜中载流子浓度梯度的产生有助于调制3C-SiC/Si异质结中的压阻效应。此外，通过评估LED光照下的横向光电压和光电流，研究了使用不同类型LED作为调制压阻效应工具的可行性。产生的横向光电压和光电流分别高达14 mV和47.2 μA。微LED在硅基器件上的直接键合的最新技术以及本文报道的发现可能会对机械传感器产生重大影响。
