Evaluation of Fe-βGa₂O₃ for Photoconductive Semiconductor Switching

Journal Article · 21 January 2024 · IEEE Transactions on Electron Devices

DOI: https://doi.org/10.1109/ted.2024.3352528 · OSTI ID:2325327

Dowling, Karen M.  ^[1]; Chatterjee, Bikramjit  ^[2]; Ghandiparsi, Soroush ^[2]; Shao, Qinghui  ^[2]; Varley, Joel ^[2]; Schneider, Joseph D.  ^[2]; Chapin, Caitlin  ^[2]; Gottlieb, Miranda S. ^[2]; Leos, Laura  ^[2]; Sword, Michael ^[2]; Harrison, Sara  ^[2]; Voss, Lars  ^[2]

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1. Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Delft Institute of Technology, Delft (Netherlands)
2. Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)

We present iron-doped beta gallium oxide (Fe- β Ga2O3) as a candidate for photoconductive semiconductor switches (PCSSs) with sub-bandgap light. From a commercially available Fe- β Ga2O3 wafer, we first did material characterization. This included measurements of absorption coefficient and dopant composition, carrier activation energy up to 200 °C, break down field of planar electrodes (limited from material passivation), and free carrier recombination lifetime, and thermal effects up to 203 °C on photocurrent with a 447 nm light emitting diode (LED) source. Here, we then demonstrated pulsed operation of a Fe- β Ga2O3 PCSS under different sub-bandgap wavelengths (355, 532, and 1064 nm) and sub-ns pulses. Fe- β Ga2O3 is a candidate for high temperature PCSS with 355 nm responsivity of 7×10^-7 A-cm/W-kV at room temperature and up to 5.5×10^-4 A-cm/W-kV at 200 °C. From these investigations, we discuss a simple trap model to describe the illumination process of the PCSS. Fe- β Ga2O3 has a high breakdown field and has moderate responsivity characteristics, but the dark current at high temperature leads to low photo-to-dark current ratio (PDCR). Regardless, we verify its potential as a PCSS material for harsh environment applications.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC52-07NA27344
• OSTI ID: 2325327
• Report Number(s): LLNL--JRNL-853779; 1081648
• Journal Information: IEEE Transactions on Electron Devices, Journal Name: IEEE Transactions on Electron Devices Journal Issue: 3 Vol. 71; ISSN 0018-9383
• Publisher: IEEECopyright Statement
• Country of Publication: United States
• Language: English