Understanding the Effects of Low-Temperature Passivation and Annealing on ZnO TFTs Test Structures

Abstract

Back-gate ZnO TFTs - with and without top-side passivation - were fabricated and electrically characterized. Passivation layers consisting of HfO2, Al2O3, and Parylene were introduced to study their impact on the TFT performance. Annealing was done to improve the electrical characteristics of passivated devices by neutralizing the initial charge introduced as a result of the low-temperature passivation. Low-temperature annealing combined with an Al2O3passivation layer demonstrates an I-V response comparable to ZnO TFTs without any passivation layer, indicating the viability of Al2O3as a good candidate for passivating ZnO TFTs.