Abstract
Dark current optimization with band gap engineering has been numerically studied for InGaAs nBn type infrared photodetectors. Undoped InAlGaAs grading layers are utilized in constructing the barrier and dipole delta-doped layers are placed in both sides of the graded layers for eliminating valence band offset. As a result, the high band gap barrier layer blocks the majority carriers and allows minority carrier flow while minimizing various dark current components, as expected from an nBn detector. Substantial improvement has been shown in the dark current level without compromising any photoresponse compared to the conventional pn junction and recently proposed all InGaAs nBn type photodetectors.
Highlights
IntroductionThe short wave infrared (SWIR) region (from 0.9 μ m to 1.7 μ m wavelength range) is quite important for both commercial and military sensing technologies with applications in science, medicine, space exploration, and security
The short wave infrared (SWIR) region is quite important for both commercial and military sensing technologies with applications in science, medicine, space exploration, and security
Results dark and photocurrent calculations including sensitivity analysis with respect to different delta-doping concentrations and various barrier heights adjusted by Al-Ga mole fraction ratio are discussed for the proposed nBn detector
Summary
The short wave infrared (SWIR) region (from 0.9 μ m to 1.7 μ m wavelength range) is quite important for both commercial and military sensing technologies with applications in science, medicine, space exploration, and security. InGaAs with a lattice-matched configuration to InP produces low enough dark current at room temperature, which makes it the most convenient choice for many applications [1–3]. Out of two main detector pixel types, planar structured devices have lower dark current due to the buried absorber layer, and mesa structured devices have some advantages such as wider application alternatives including dual/multicolor implementation and lower crosstalk due to the isolated pixels [4, 5]. In order to optimize the dark current performance, many methods including post pixel processing passivation and various epilayer designs have been developed, but none of these techniques have fully eliminated the leakage at the surface [6–12]. Recently, barrier structured detectors have been numerically and experimentally shown to produce lower dark current than conventional pn junction detectors and to operate at higher operation temperatures [13–35]. To be able to achieve this, various techniques such as simultaneous grading of composition and doping concentration, p-type doped barriers, superlattice
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: TURKISH JOURNAL OF ELECTRICAL ENGINEERING & COMPUTER SCIENCES
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
