Leakage mechanisms and potential performance of molecular-beam epitaxially grown GaInAsSb 2.4 μm photodiode detectors

Abstract

We report on the growth, processing, and characterization of uncoated, unpassivated GaInAsSb detector mesa photodiodes with a cutoff wavelength of 2.4 μm. We find peak room temperature specific detectivity value of 6×1010 cm Hz1/2/W and maximum zero-bias resistivity of 25 Ω cm2. The zero-bias resistivities of mesas with areas ranging from 502 μm2 to 1 mm2 were found to be limited by generation-recombination currents at mesa sidewalls. At low temperatures, devices were limited by Ohmic leakage, which is likely due to the formation of oxides on the sidewalls. After 6 months of aging, Ohmic leakage becomes the limiting factor at room temperature as well. Based on experimentally obtained material parameters in this and other studies, an upper limit D∗ and R0A were estimated for GaInAsSb materials and compared to those HgCdTe and InGaAs.

Heterogeneous Integration of GaInAsSb p-i-n Photodiodes on a Silicon-on-Insulator Waveguide Circuit

“…25 Ω. cm 2 is obtained on these devices. The overall performance of this device is not as good as the previous reports on stand-alone non-integrated devices [3], [15]. This is due to the smaller size of the current device which experiences more side wall and therefore results in higher leakage current.…”

Short-wave infrared GaInAsSb photodiodes grown on GaAs substrates

“…The value of 260 Ωcm 2 obtained from the dry-etched photodiodes studied in this work is notably higher than values reported in the literature for GaInAsSb diodes grown directly on GaSb substrates. 8,9,10 It would be expected that diodes grown directly on GaSb substrates should have fewer threading dislocations and hence better electrical properties, including a higher R 0 A. However it must be noted that the R 0 A product ultimately achieved in a finished photodiode can depend on many factors relating to growth and fabrication, which are not evident when comparing publications.…”

“…These D* values approach the best results reported for GaInAsSb detectors grown on GaSb substrates. 8,9,10 Furthermore they could be readily enhanced by the addition of an antireflection coating. Additional improvements can be foreseen if the responsivity suppression at 0 V is eliminated, and if a more extensive program of growth development is undertaken to optimize the GaInAsSb alloy.…”

“…Finally the quaternary alloy GaInAsSb has shown promising results and can be grown lattice matched to GaSb with compositions tuned to cover the spectral range between 1.7 and 2.6 μm. 8,9,10 The use a quaternary alloy brings challenges with regard to controlling composition, however lattice matched grown promises the potential for low defect densities, and the use of standard III-V growth and processing equipment promises relatively low costs and universal technological access. Driven by these potential advantages this work focuses on the use of GaInAsSb in SWIR photodiodes.…”

Phase separation and defect formation in stable, metastable, and unstable GaInSaSb alloys for infrared applications

“…Figure 1.1 shows the lattice constant and band gap values of select binary III-V semiconductors [1]. Quaternary alloys such as GaInAsSb/AlGaAsSb are a material system of importance for infrared optoelectronics [2], particularly lasers, [3][4][5], but also light-emitting diodes, [6,7] photodiode detectors, [8,9] and thermophotovoltaics. [10].…”