Extended-wavelength 1.3-megapixel type-II superlattice SWIR compact camera system with scalable manufacturing

Ettenberg, M.; Dianat, Pouya; Lange, Michael; Sudol, Thomas M.; Nguyen, Hai; Gil, A.; Ahmed, Nuha; Phillips, J. E.

doi:10.1117/12.2614565

Cited by 2 publications

(2 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, the use of a diffusion process to introduce the selective area doping is more suitable, which is also less damaging to the T2SL structure and less expensive compared to ion-implantation. Although the planar photodetectors based on HgCdTe, InP, InAsSb, InSb and GeSn bulk materials have been reported before, few T2SLs-based planar devices have been demonstrated [22][23][24][25][26][27][28][29]. These T2SLs-based planar photodetectors showed promising performance results but still need to be further improved [30][31][32].…”

Section: Introductionmentioning

confidence: 99%

High Performance Planar Antimony-Based Superlattice Photodetectors Using Zinc Diffusion Grown by MBE

Saroj

Slivken

et al. 2022

Photonics

View full text Add to dashboard Cite

In this letter, we report a mid-wavelength infrared (MWIR) planar photodetector based on InAs/InAs1−xSbx type-II superlattices (T2SLs) that has a cut-off wavelength of 4.3 μm at 77 K. The superlattice for the device was grown by molecular beam epitaxy while the planar device structure was achieved by Zinc diffusion process in a metal–organic chemical vapor deposition reactor. At 77 K, the peak responsivity and the corresponding quantum efficiency had the value of 1.42 A/W and 48% respectively at 3.7 μm under −20 mV for the MWIR planar photodetector. At 77 K, the MWIR planar photodetector exhibits a dark current density of 2.0 × 10−5 A/cm2 and the R0A value of ~3.0 × 102 Ω∙cm2 under −20 mV, which yielded a specific detectivity of 4.0 × 1011 cm·Hz1/2/W at 3.7 μm. At 150 K, the planar device showed a dark current density of 6.4 × 10−5 A/cm2 and a quantum efficiency of 49% at ~3.7 μm under −20 mV, which yielded a specific detectivity of 2.0 × 1011 cm·Hz1/2/W.

show abstract

Section: Introductionmentioning

confidence: 99%

High Performance Planar Antimony-Based Superlattice Photodetectors Using Zinc Diffusion Grown by MBE

Saroj

Slivken

et al. 2022

Photonics

View full text Add to dashboard Cite

show abstract

“…Lattice matched InGaAs/GaAsSb T2SL on InP substrates has also been used for detection in the SWIR region up to 2.0 µm with high operating temperatures using wider bandgap alloy compositions compatible with the InP substrate [8][9]. 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%

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

Extended-wavelength 1.3-megapixel type-II superlattice SWIR compact camera system with scalable manufacturing

Cited by 2 publications

References 10 publications

High Performance Planar Antimony-Based Superlattice Photodetectors Using Zinc Diffusion Grown by MBE

High Performance Planar Antimony-Based Superlattice Photodetectors Using Zinc Diffusion Grown by MBE

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

Contact Info

Product

Resources

About