Comprehensive Study of Surface Defects in Traditional Type-II InAs/GaSb Superlattices and Ga-free Type II_Research Area 4 3 Electronic Sensing
Abstract
This article serves as the progress report of the first quarter of year 2015 Leakage currents limit the operation of high performance type II InAs/GaSb superlattice-based photodiodes. Surface leakage current becomes a dominant limiting factor, especially for small pixel pitch focal plane arrays (< 25 micrometer), and must be addressed. Strategies for controlling surface leakage current include reduction of the surface trap state density, unpinning the Fermi level at the surface, and appropriate termination of the semiconductor crystal. This report focuses on influence of SiO2 passivation of type II InAs\GaSb superlattice-based photodetectors on surface leakage current and, subsequently, total dark current density of the devices. Our analysis indicates that deposition of SiO2 enhances the surface trap energy state level, which results in an improvement in device electrical performance under small bias voltages (|Vbias|<200mV). However, the dark current density increased under larger bias voltages as a consequence of increased surface trap density on oxide-semiconductor interface.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 2018
- Accession Number
- AD1067226
Entities
People
- Manijeh Razeghi
Organizations
- Northwestern University