Electrical and Computer Engineering ETDs

Publication Date

Fall 11-9-2023


The performance of the mid-wave infrared InGaAs/InAsSb nBn photodetector is investigated and its viability for space applications is assessed. Three structures are grown with unique absorber layer doping profiles via molecular beam epitaxy. Material and device characterizations are performed and analyzed to determine the effects of doping on fundamental material parameters and detector performance. Noise-equivalent irradiance is calculated to be a factor of 4x that of an ideal detector exhibiting Rule 07 dark current and 100% quantum efficiency, demonstrating high sensitivity. The structures are then irradiated with 63 MeV protons to evaluate the extent of performance degradation over the course of mission lifetime within the space environment. The graded doping profile structure exhibits high sensitivity and resiliency to performance degradation, thereby demonstrating viability to satisfying the growing demand of a scalable mid-wave infrared sensor for space applications.

In-depth characterization analysis and development of fitting tools offer insight into the properties of the InGaAs/InAsSb superlattices and their evolution with proton fluence. This allows for a fundamental perspective into the mechanisms driving the observed trends in detector performance, providing a path forward to further technological improvement.


Photodetector, III-V, MWIR, Diffusion, dark current, quantum efficiency

Document Type




Degree Name

Electrical Engineering

Level of Degree


Department Name

Electrical and Computer Engineering

First Committee Member (Chair)

Ganesh Balakrishnan

Second Committee Member

Payman Zarkesh-Ha

Third Committee Member

Christos Christodoulou

Third Advisor

Christian Morath

Fourth Committee Member

Preston Webster

Fifth Committee Member

Adam Hecht