Amorphous indium tin oxide transistors for power amplification above 10 GHz

Amorphous oxide semiconductors could be used as thin channel materials in future back-end-of-line-compatible electronics. However, thin body amorphous materials suffer from Joule heating due to the strong scattering of electrons and phonons from extensive local disorder, which can lead to device failure in high-speed power-intensive applications. Here we show that the electrical and thermal transport properties of amorphous indium tin oxide can be enhanced using a silicon carbide substrate. Using this approach, we create top-gate transistors that have a channel length of 120 nm and exhibit negligible performance degradation under high electric fields and temperatures of up to 125 °C. We show that the devices can offer a cutoff frequency of 103 GHz and a maximum oscillation frequency of 125 GHz. Furthermore, our indium tin oxide power amplifiers provide a high output power density of 0.69 W mm−1 and a power-added efficiency of 24.1% at 12 GHz. The electrical and thermal transport properties of amorphous indium tin oxide can be enhanced by using a silicon carbide substrate, leading to indium tin oxide power amplifiers with an output power density of 0.69 W mm−1 and a power-added efficiency of 24.1% at 12 GHz.