Black Germanium Photodetector Exceeds External Quantum Efficiency of 160%
- The development of reliable methods to fabricate nanostructured semiconductor materials is important in the creation of advanced optoelectronic devices including photodetectors.
- Prof. Kim Munho and his team built the germanium pyramids, which are 150 nm wide and 570 nm high, using a room-temperature chlorine-gas-based reactive ion etching process that takes only 2 min.
- The nanostructuring reduces the average light reflectance from 37% for a pristine planar germanium wafer to 2%. The enhanced light trapping created by this geometry leads to improved absorption and a responsiveness of 2.01 A W–1, which is two and a half times higher than the responsiveness of non-structured germanium.


Our work was exclusively featured by Research Highlight of Nature Electronics (IF: 33.686)

High performance flexible visible-blind UV optical sensors with 2DEG based on unconventional release strategy
- Flexible UV sensors based on the two-dimensional electron gas (2DEG) at the interface of AlGaN/GaN heterostructure membranes have been firstly fabricated using AlGaN/GaN on insulator substrates via an unconventional release strategy.
- Under a range of external strains (compressive, flat, and tensile), the sensors recorded a responsivity level of 100 times higher than existing UV sensors. This responsivity remained stable after 100 cycles of repetitive bending, demonstrating its potential to be integrated into wearables.


