Viterbi Faculty of Electrical Engineering, Technion
Toward GaN on Si-based Monolithic integrated inter-subband IR optoelectronics
We present for the first time a CMOS process-compatible intersubband transition (ISBT) infrared (IR) detector epitaxially selectively grown on Si wafers. Integrated, CMOS-compatible IR detectors are very desirable, since they will revolutionize applications such as autonomous vehicles, defense, and optical communications. Currently, the fabrication of IR detectors for imaging requires separate processes for driving the electronics and detecting pixel arrays, which significantly augments the complexity and cost of the system, and hinders the wide adoption of IR sensing systems.
Optical ISBT in quantum wells (QWs) are transitions that take place entirely within the conduction band; they have been used in a variety of applications such as ultrafast electro-optic devices, all-optical switching, Quantum Well Infra-Red Photodetectors (QWIPs), both Near (NIR) and Mid (MIR) IR range, and Quantum Cascade Lasers (QCLs). III-Nitride materials allow the transition wavelength to be tuned by changing the QW width across the IR range. Using these materials, one can design a Quantum Cascade Detector (QCD)-based IR sensor that utilizes internal electric fields to enable zero-voltage operation and reduce the Noise Equivalent Power (NEP). Among the III-V material systems, only the Gallium-Nitride (GaN) system is a mature and proven technology for epitaxial growth on Si and for standard CMOS-compatible fabrication. This offers the possibility to have the detector be in-plane with the readout CMOS IC, but only if the GaN structure can be grown selectively using a thermal budget that is CMOS process compatible.
In my talk I will briefly explain the challenges of developing monolithic integrated GaN-based QCDs with CMOS IC, and I will present our progress towards achieving a complete circuit. I will present results that demonstrate operational MIR QCDs selectively grown using a CMOS-compatible process and our latest results in improving the detectivity of such devices. In addition, I will show measurement and simulation results that support our claim that the process is CMOS compatible, and lastly, I will present experimental data for NIR QCDs using the same material system.
* M.Sc. student under the supervision of Prof. Gad Bahir and Prof. Meir Orenstein.
Join Zoom Meeting: https://technion.zoom.us/j/91782314073
Mon 19 Apr 2021
Start Time: 14:30
End Time: 15:30
Zoom meeting | Electrical Eng. Building