Perovskite transistors work longer with a better insulator

Abstract

Perovskites have received a lot of attention as semiconductor materials for solar cells because they’re inexpensive and easy to make. But attempts to make transistors using perovskites have resulted in devices that quickly stop working. Now, by swapping out the insulating material, researchers have made perovskite transistors that work much longer than past devices (ACS Mater. Lett. 2019, DOI: 10.1021/acsmaterialslett.9b00357). Transistors are electronic switches that flip between the 1 and 0 of digital logic. In these devices, a voltage applied at a gate electrode turns the flow of current on and off through a channel made of a semiconductor such as silicon. An insulating layer—traditionally silicon dioxide—protects the channel from the gate voltage. A team led by Aditya D. Mohite of Rice University instead made transistors with a more effective insulating material, hafnium dioxide, and used the perovskite methylammonium lead iodide as the channel semiconductor. Changing the insulator overcame a