Flexibility of Ga-containing Type-II superlattice for long-wavelength infrared detection

Abstract

In this paper, the flexibility of long-wavelength Type-II InAs/GaSb superlattice (Ga-containing SL) is explored and investigated from the growth to the device performance. First, several samples with different SL period composition and thickness are grown by molecular beam epitaxy. Nearly straincompensated SLs on GaSb exhibiting an energy band gap between 105 to 169 meV at 77K are obtained.Second, from electronic band structure calculation, material parameters are extracted and compared for the different grown SLs. Finally, two p-i-n device structures with different SL periods are grown and their electrical performance compared. Our investigation shows that an alternative SL design could potentially be used to improve the device performance of diffusion-limited devices for long-wavelength infrared detection.

Monolithic integration of a 10 μm cut-off wavelength InAs/GaSb type-II superlattice diode on GaAs platform

“…As Fig. 5 c shows, Sample C is dominated by diffusion currents at temperatures above 120 K and G-R currents in the temperature range 100 K–120 K in a manner consistent with previously reported devices 47 , 63 . At temperatures below 100 K, the measured dark current density deviates from the fitted G-R-dominated behavior, possibly due to the presence of other sources of dark current such as trap assisted tunneling (TAT) or shunt currents.…”

“…Two 12/4 SL reference samples were grown by Molecular Beam Epitaxy (MBE) on a GaSb substrate (Sample A) and a GaAs substrate using the IMF array (Sample B). The structures of these samples have been reported previously 45 , 47 . Photoluminescence (PL) measurements, shown in Fig.…”

“…This report aims to determine the efficacy of the IMF array by growing a p-i-n diode with a 12 ML InAs/ 4 ML GaSb (12/4) SL on a GaAs substrate. We have demonstrated a lower diffusion current in a 12/4 SL at 150 K in comparison to the most commonly used 14/7 SL 47 . Enhancement in electron–hole wavefunction overlap and absorption coefficient in the 12/4 SL suggests its suitability for high performance 10 μm optoelectronic applications such as photodetectors, LEDs, and lasers 47 .…”

“…We have demonstrated a lower diffusion current in a 12/4 SL at 150 K in comparison to the most commonly used 14/7 SL 47 . Enhancement in electron–hole wavefunction overlap and absorption coefficient in the 12/4 SL suggests its suitability for high performance 10 μm optoelectronic applications such as photodetectors, LEDs, and lasers 47 . More recently, we have also reported on the structural and optical quality of a 12/4 SL grown directly on GaAs substrates 44 .…”

Effect of Interfacial Schemes on the Optical and Structural Properties of InAs/GaSb Type-II Superlattices

“…In line with Livneh et al, the IF parameters α and β were fixed at 0.2 eV·Å. The diagonal IF parameters D s , D x , and D z , were chosen for best agreement with PL results from previously reported SL structures . The parameters used for InAs, GaSb, and InSb can be found elsewhere .…”