Fig. 3: Device characteristics of volatile DG MPBTFT for physical reservoir.
From: Analog reservoir computing via ferroelectric mixed phase boundary transistors
a Schematic illustration and cross-sectional view of the volatile DG MPBTFT. The DG MPBTFT operates as an MPBTFT with an MFMIS structure and a TFT with an MIS structure at the BG and TG sides, respectively. b Cross-sectional TEM images of the fabricated DG MPBTFT. c Top optical images of the DG MPBTFT array. The DG MPBTFT array has WL pairs (WLB and WLT) parallel to each other, each connected to the BG and TG electrodes of the DG MPBTFT within the array. The width (W) and length (L) of a channel are both 20 μm. d Switching current and P-V hysteresis loop through triangular pulses with 100 kHz. e Hysteretic transfer characteristics (ID-VBG) for various TG voltage (VTG) conditions. Bidirectional DC sweeps of the BG voltage (VBG), ranging from –2.0 V to 2.0 V, were performed at a VDS of 0.1 V. f Decay characteristics of the ID over time, subsequent to the application of a 100 μs PGM pulse. The relaxation processes are well-fitted for various VPGMs through a double exponential function (red lines). g ID response according to various VTGs when a constant pulse train (4.0 V, 100 μs) is applied to the BG. ID evolutions in response to 16 different input pulse trains (4.0 V, 100 μs) h without and i with TG utilization. Each input pulse train comprises 4 timeframes with a 3 ms time interval between successive pulses. The upper panel shows the pulse schemes for the BG and TG (e.g., input ‘1111’). By applying gradually decreasing voltage pulses across 4 timeframes to the TG, clearly distinguishable reservoir states are generated for various input data. j ID evolutions in response to 32 different input pulse trains (4.0 V, 100 μs), each comprising 5 timeframes. The upper panel shows the pulse schemes for the BG and TG (e.g., input ‘11111’). The utilization of the TG effectively expands the reservoir states.
