Si-based infrared up-converting devices

Supervisor: Dr. Lyudmila Goncharova/Peter Simpson

Project Description (Abstract):

Infrared (IR) imaging is central in numerous applications such as night vision, environmental monitoring, surveillance, and even spectroscopy and biomedical applications. Although IR imaging is becoming prevalent, the high production cost has been a major obstacle in the developing of high-resolution IR imaging sensors. Current IR detector arrays are manufactured of quantum well heterostructures (InGaAs, InSb and HgCdTe) which are expensive and difficult to scale. This project will focus on developing a cost-effective versatile and scalable IR imaging device directly integrated on silicon. As illustrated below, this device acts as an IR sensor capable of converting light from 0.5-3 um (IR) to visible light at ~ 650 nm which then can be detected by common visible light sensors.

In this project, we will combine IR sensor based on Si_1-xGe_x or Si_xGe_1-x-ySn_y alloys with Si-based light emitting structure. This device will use photon up-conversion to convert photons from low to high frequencies. We propose to use Si-based light emitting structures, consisting of Si quantum dots (QD) in silicon oxide or silicon nitride layer between two electrode layers. Our group has demonstrated effective light emitting properties of Si QD in different dielectric materials, and this project will focus on manufacturing of functional Si quantum dot light-emitting diodes (QD LEDs). We also used an molecular beam epitaxy (MBE) deposition system to produce Si_1-xGe_x allow structures. We plan to start with Si_xGe_1-x alloys and demonstrate light detection capabilities in 0.5-1.4um. Graduate student will work on optimization of the Si_1-xGe_x or Si_xGe_1-x-ySn_y heterostructure growth by MBE to be used as IR detectors.