Growth of antimonide IR detectors in MOCVD technology Krzysztof Kłos 1,*,  @Photin_MOCVD  kk@photin.eu Karel Melichar2 Jiri Pangrac2 Alice Hospodkova2 Paweł Michałowski3 1 Photin LLC, Poland www.photin.eu, 2 Institute of Physics CAS, v.v.i., Czech Republic www.fzu.cz 3 Łukasiewicz-IMiF Poland, Introduction Semiconductors from so called 6.1A group GaSb-InAs-AlSb are having unique features such as high mobility, type 2 bandgap lineup, which makes them attractive materials for high- end applications in solar cells, thermophotovoltaic cells, IR emitters, IR detectors, TFET transistors or new types of RAM memory(UltraRAM). This work share information about growth of GaSb, lattice matched InGaAsSb and AlGaAsSb on (100) GaSb substrates in Aix-200 horizontal MOCVD reactors: 1) assisted by Reflectance Anisotropy Spectroscopy (RAS) in-situ monitoring.[1], [2]. 2) standard Aix-200 RF without in-situ monitoring The target layer structure to be developed is eSWIR barrier detector structure aimed at unbiased operation at 300K. This kind of structures were intensively analyzed, developed and optimized[3], due to yield of ~50% with so called “extended InGaAs/InP”(fig. 2a VIGO@IC-MOVPEXX2022). InGaAsSb/AlGaAsSb structures were grown in MOCVD by Wang[4] and Dutta et al.[5], and in MBE [3], [6], [7]. GaSb AlGaSb AsGaSb InGaSb AlGaAsSb InGaAsSb p 2e18 cm-3 N-GaSb (Te) substr. GaSb buffer InGaAsSb base InGaAsSb absorber AlGaAsSb barrier GaSb 0.5µm 0.3µm 2.0µm 0.3µm 0.1µm Thickness Doping n 1e18 cm-3 n 2e18 cm-3 n 2e17 cm-3 undoped undoped Layers Figure 1: a) development matrix of GaSb-based ternary and quaternary compounds, b) layer structure of eSWIR detector The best results reported in literature so far were processed in Lancaster University by Laura Hanks[3] in ams-OSRAM project, as could be seen on fig. 2b. Figure 2: a) development matrix of GaSb-based ternary and quaternary compounds, b) layer structure of eSWIR detector Experimental - Material Growth The GaSb based structures were grown in an AIXTRON Aix-200 system horizontal quartz reactors for 1x 2” wafer with RF heaters, details of the growths with RAS monitoring were reported earlier[8]. The most of runs were dedicated to optimization of buffer GaSb growth. Results Figure 3: Comparison of buffers grown by Photin - Nomarsky contrast. Figure 4: a) In-situ RAS and Reflectance. b) HR XRD profile of full structure grown. The In-Situ monitoring is not so sensitive for mismatch (fig. 4a). HR XRD profile shows mismatch ~3200ppm, which cause elevated dark current of processed devices. Figure 5: Comparison of pictures with Nomarsky on FZU(left) and Photin(right) GaSb buffers. Figure 6: a) High resolution SIMS profile of barrier region and their neighbourhood. b) T2SLs GaSb/InAs trial monitored by In Situ RAS The SIMS measurement reveal proper, Al composition profile, correct Zn profile, extremely stable and steep Te doping profile transitions (fig. 6a) in critical region of devices. Figure 7: Two processing schemes were tested: planar (top), and mesa (bottom). Conclusions 1. Technological conditions were explored for the growth and doping of complex IR detector structure consisting GaSb, InGaAsSb and AlGaAsSb layers. 2. Processing and full characterization of grown eSWIR epi-structures 3. Developed technology is being optimized by Photin. References [1] A. Hospodková et al., “Growth of InAs/GaAs quantum dots covered by GaAsSb in multiple structures studied by reflectance anisotropy spectroscopy,” Journal of Crystal Growth, vol. 414, pp. 156–160, Mar. 2015, doi: 10.1016/j.jcrysgro.2014.10.026. [Online]. Available: https://linkinghub.elsevier.com/retrieve/pii/S0022024814007118. [Accessed: 06-Jun-2022] [2] K. Möller et al., “In-situ monitoring and analysis of GaSb(100) substrate deoxidation,” Applied Surface Science, vol. 242, no. 3–4, pp. 392–398, Apr. 2005, doi: 10.1016/j.apsusc.2004.09.006. [Online]. Available: https://linkinghub.elsevier.com/retrieve/pii/S0169433204013376. [Accessed: 06-Jun-20