High-performance and low-power source-gated transistors enabled by a solution-processed metal oxide homojunction

Abstract

Cost-effective fabrication of mechanically flexible low-power electronics is important for emerging applications including wearable electronics, artificial intelligence, and the Internet of Things. Here, solution-processed source-gated transistors (SGTs) with an unprecedented intrinsic gain of ~2,000, low saturation voltage of +0.8 ± 0.1 V, and a ~25.6 μW power consumption are realized using an indium oxide In 2 O 3 /In 2 O 3 :polyethylenimine (PEI) blend homojunction with Au contacts on Si/SiO 2 . Kelvin probe force microscopy confirms source-controlled operation of the SGT and reveals that PEI doping leads to more effective depletion of the reverse-biased Schottky contact source region. Furthermore, using a fluoride-doped AlO x gate dielectric, rigid (on a Si substrate) and flexible (on a polyimide substrate) SGTs were fabricated. These devices exhibit a low driving voltage of +2 V and power consumption of ~11.5 μW, yielding inverters with an outstanding voltage gain of >5,000. Furthermore, electrooculographic (EOG) signal monitoring can now be demonstrated using an SGT inverter, where a ~1.0 mV EOG signal is amplified to over 300 mV, indicating significant potential for applications in wearable medical sensing and human–computer interfacing.

Ultrahigh-gain organic transistors based on van der Waals metal-barrier interlayer-semiconductor junction

“…1H and table S1. The statistical results show that the MBIS-OTFTs achieve ultrahigh intrinsic gain of ~10 4 and operate in ON-state region, which is superior to previous TFT reports ( 11 – 13 , 18 , 21 , 30 , 31 ).…”

High gain complementary inverters based on comparably-sized IGZO and DNTT source-gated transistors

“…30 At high absolute gate-source voltage, both transistors exhibit negative differential resistance in the output curves. This has been observed in several SGT implementations 26,30,32 and will be investigated separately. Nevertheless, flat output characteristics are obtained across a large range of operating conditions.…”

Flexible and Stretchable Organic Electrochemical Transistors for Physiological Sensing Devices

“…The ion intake/outtake and the redox process vary the electronic carrier density in the semiconductor modulating the electronic conductivity of the channel upon application of V GS /V DS biases (Figure 1c). [89] Consequently, a volumetric capacitance is associated with OECT operation, which is typically orders of magnitude higher than that in typical OFETs/OEDLTs, [90][91][92][93][94] as well as solution processed metal oxide FETs/EDLTs, [95][96][97][98][99][100][101] leading to a large amplification capability at low driving voltages (typically <1 V for aqueous electrolyte). [42,71] Figure 1d compares the g m range of OFETs, OEDLTs, and OECTs versus driving voltage, but note, the driving voltages of OFETs are typically much larger than the 5 V reported in this figure . The most advanced OECTs reported to date are based on ptype (hole-transporting or electrochemically oxidized) semiconductors, while n-type (electron-transporting or electrochemically reduced)-semiconductor-based OECTs remain rare, are typically less stable, and exhibit much lower performance compared to their p-type counterparts.…”

“…The ion intake/outtake and the redox process vary the electronic carrier density in the semiconductor modulating the electronic conductivity of the channel upon application of V GS / V DS biases (Figure 1c). [ 89 ] Consequently, a volumetric capacitance is associated with OECT operation, which is typically orders of magnitude higher than that in typical OFETs/OEDLTs, [ 90–94 ] as well as solution processed metal oxide FETs/EDLTs, [ 95–101 ] leading to a large amplification capability at low driving voltages (typically <1 V for aqueous electrolyte). [ 42,71 ] Figure 1d compares the g m range of OFETs, OEDLTs, and OECTs versus driving voltage, but note, the driving voltages of OFETs are typically much larger than the 5 V reported in this figure.…”