Bandgap Engineering and Short-Wavelength Infrared Detection of InGaAs/GaAsSb Superlattices Lattice-Matched to InP

Gil, Armando; Phillips, Jamie; Ettenberg, M.; Babikir, Nuha A.

doi:10.1007/s11664-022-09745-x

Cited by 2 publications

(3 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 3(b) shows the effect of varying period thickness for a fixed strain-balanced composition of In0.52Ga0.48As / GaAs0.48Sb0.52. Previous studies on the lattice matched case for symmetrical periods showed increase in absorption strength at the cutoff with reduced period thickness and increase in cutoff wavelength with increased thicker periods [11]. The green curve shows the reference T2SL structure used in the simulation and device fabrication for this study of 4.73 nm In0.52Ga0.48As / 4.50 nm GaAs0.48Sb0.52.…”

Section: Effect Of Period Thickness and Strainmentioning

confidence: 97%

“…Recent work that utilized lattice matched InGaAs/GaAsSb superlattices as an absorber material that has been incorporated in a 1.68 megapixel commercial imager demonstrated achievable dark current densities of 4.8 mA/cm 2 at -0.1V and quantum efficiency greater than 30% over 1.2-1.8 µm and a cutoff of 2.2 µm [10]. Limitations for using lattice matched InGaAs/GaAsSb superlattices is that extending wavelength requires thicker periods (quantum well and barrier) while thicker periods lower optical absorption strength [11].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Strain-balanced InGaAs/GaAsSb type-II superlattices on InP for extended short-wavelength infrared detection

Ahmed-Babikir

Phillips²,

Ettenberg³

et al. 2023

Physics and Simulation of Optoelectronic Devices XXXI

Self Cite

View full text Add to dashboard Cite

Extending the wavelength response of short-wavelength infrared detectors (SWIR) to 2 µm and beyond offers a key enabling technology for Lidar, spectroscopy, and imaging applications. Lattice-matched InGaAs/GaAsSb type-II superlattices (T2SL) have demonstrated SWIR detection around 2 µm on a highly producible InP platform but are limited in further extending wavelength response out to 2.5 µm. Introducing strain between alternating periodic layers of the superlattice provide a means to further extend wavelength while maintaining a strain balance (net zero strain). Numerical modeling utilizing 8 band k.p simulations were studied to examine the impact of bandgap energy, quantum confinement, and strain on the effective bandgap, wavefunction overlap, and corresponding absorption strength. T2SL with 4.73 nm In0.52Ga0.48As and 4.5 nm GaAs0.48Sb0.52 demonstrate extended wavelength response with absorption coefficient ~1000 cm -1 around the cutoff wavelength and over most of the 2-2.5 µm range indicating efficient overlap between the wavefunctions and high quantum efficiency values. Effect of period thickness, and strain on absorption coefficient and effective bandgap is analyzed and compared with the lattice matched case. Devices were fabricated with the superlattice structure as the absorber layer (3 µm thick) in a p-i-n photodiode configuration. Dark current voltage characteristics were measured and compared with simulated results. Measured dark current values were comparable to those of lattice-matched InGaAs/GaAsSb type II superlattices without extensive device optimization. Simulated quantum efficiency results showed clear extended cutoff of 2.5 µm with high quantum efficiency values in the 1.4-2.1 µm spectral region and features that closely follow absorption spectra validating the suitability of the strainbalanced approach in reducing the effective bandgap values while maintain absorption strength.

show abstract

Section: Effect Of Period Thickness and Strainmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

Strain-balanced InGaAs/GaAsSb type-II superlattices on InP for extended short-wavelength infrared detection

Ahmed-Babikir

Phillips²,

Ettenberg³

et al. 2023

Physics and Simulation of Optoelectronic Devices XXXI

Self Cite

View full text Add to dashboard Cite

show abstract

“…In recent years, a newly developed material system, type II superlattice (T2SL) structure, has been exploited to work across the SWIR spectral band range. Photodetectors based on the T2SL system not only obtain the ability to cover wide range spectral band as MCT counterparts, representing great flexibility in band engineering [ 8 , 9 ], but also show advantages in suppressing auger recombination and have a high crystal quality [ 10 , 11 ]. Nevertheless, more complicated growth conditions for abrupt interfaces with suppressed intermixing of As/Sb are required in the case of ultrathin superlattices.…”

Section: Introductionmentioning

confidence: 99%

Growth and Dark Current Analysis of GaSb- and InP-Based Metamorphic In0.8Ga0.2As Photodetectors

et al. 2023

View full text Add to dashboard Cite

Short-wavelength infrared photodetectors based on metamorphic InGaAs grown on GaSb substrates and InP substrates are demonstrated. The devices have a pBn structure that employs an AlGaAsSb thin layer as the electron barrier to suppress dark current density. The strain effect on the electrical performance of the devices was specifically studied through the growth of the pBn structure on different substrates, e.g., InP and GaSb, via a specific buffering technique to optimize material properties and minimize dark current. A lower device dark current density, down to 1 × 10−2 A/cm2 at room temperature (295 K), was achieved for the devices grown on the GaSb substrate compared to that of the devices on the InP substrate (8.6 × 10−2 A/cm2). The improved properties of the high-In component InGaAs layer and the AlGaAsSb electron barrier give rise to the low dark current of the photodetector device.

show abstract

Bandgap Engineering and Short-Wavelength Infrared Detection of InGaAs/GaAsSb Superlattices Lattice-Matched to InP

Cited by 2 publications

References 13 publications

Strain-balanced InGaAs/GaAsSb type-II superlattices on InP for extended short-wavelength infrared detection

Strain-balanced InGaAs/GaAsSb type-II superlattices on InP for extended short-wavelength infrared detection

Growth and Dark Current Analysis of GaSb- and InP-Based Metamorphic In0.8Ga0.2As Photodetectors

Contact Info

Product

Resources

About