Near-IR multi-quantum-well SiGe detectors show promise for photonics integration

April 4, 2012
High-quality single-crystal silicon-germanium (SiGe) multi-quantum-well layers were epitaxially grown on silicon substrates by researchers at Bilkent University, the Massachusetts Institute of Technology, Korea University, and the Masdar Institute of Science and Technology.

High-quality single-crystal silicon-germanium (SiGe) multi-quantum-well layers were epitaxially grown on silicon substrates by researchers at Bilkent University (Ankara, Turkey), the Massachusetts Institute of Technology (Cambridge, MA), Korea University (Seoul, South Korea), and the Masdar Institute of Science and Technology (Abu Dhabi, UAE). The layers were fashioned into mesa-structured p-i-n photodetectors functioning at telecommunications wavelengths with reverse leakage currents of about 10 mA/cm2 and responsivities above 0.1 A/W in the 1300 to 1600 nm range. The spectral response of the photodetectors was voltage-tunable via altering the reverse bias, shifting the absorption edge by tens of nanometers.

The creation of GeSi devices on silicon is important for large-scale optical and optoelectronic circuits, as SiGe fabrication is compatible with complementary metal-oxide semiconductor (CMOS) technologies used to fabricate silicon computer chips. The ten quantum wells for the p-i-n detectors consisted of 10-nm-thick germanium wells and 20-nm-thick Si0.1Ge0.9 barriers, with the strained germanium lattice contributing to a high light absorption. Photodiodes were made with mesa diameters ranging between 20 and 120 μm; for devices with mesa areas less than 100 μm2, the RC time constant was estimated to be below one picosecond. Contact Ali Okyay at [email protected].

Sponsored Recommendations

How Precision Motion Systems are Shaping the Future of Semiconductor Manufacturing

March 28, 2024
This article highlights the pivotal role precision motion systems play in supporting the latest semiconductor manufacturing trends.

Understanding 3D Printing Tolerances: A Guide to Achieving Precision in Additive Manufacturing

March 28, 2024
In the world of additive manufacturing, precision is paramount. One crucial aspect of ensuring precision in 3D printing is understanding tolerances. In this article, we’ll explore...

Automation Technologies to Scale PIC Testing from Lab to Fab

March 28, 2024
This webinar will cover the basics of precision motion systems for PIC testing and discuss the ways motion solutions can be specifically designed to address the production-scale...

Case Study: Medical Tube Laser Processing

March 28, 2024
To enhance their cardiovascular stent’s precision, optimize throughput and elevate part quality, a renowned manufacturer of medical products embarked on a mission to fabricate...

Voice your opinion!

To join the conversation, and become an exclusive member of Laser Focus World, create an account today!