Implementation of Low-Power Electronic Devices Using Solution-Processed Tantalum Pentoxide Dielectric

The development of solution-processed field effect transistors (FETs) based on organic and hybrid materials over the past two decades has demonstrated the incredible potential in these technologies. However, solution processed FETs generally require impracticably high voltages to switch on and off, which precludes their application in low-power devices and prevent their integration with standard logic circuitry. Here, a universal and environmentally benign solution-processing method for the preparation of Ta₂O₅, HfO₂ and ZrO₂ amorphous dielectric thin films is demonstrated. High mobility CdS FETs are fabricated on such high-κ dielectric substrates entirely via solution-processing. The highest mobility, 2.97 cm² V⁻¹ s⁻¹ is achieved in the device with Ta₂O₅ dielectric with a low threshold voltage of 1.00 V, which is higher than the mobility of the reference CdS FET with SiO₂ dielectric with an order of magnitude decrease in threshold voltage as well. Because these FETs can be operated at less than 5 V, they may potentially be integrated with existing logic and display circuitry without significant signal amplification. This report demonstrates high-mobility FETs using solution-processed Ta₂O₅ dielectrics with drastically reduced power consumption; ≈95% reduction compared to that of the device with a conventional SiO₂ gate dielectric.