Environmental, Thermal, and Electrical Susceptibility of Black Phosphorus Field Effect Transistors

TL;DR

This study systematically investigates how environmental factors, thermal, and electrical treatments affect black phosphorus field-effect transistors, revealing unique degradation mechanisms and the need for tailored stability procedures.

Contribution

It provides a comprehensive analysis of environmental and treatment effects on black P FETs, highlighting differences from other 2D materials and emphasizing the need for specialized stability protocols.

Findings

Device performance degrades under ambient light, air, and humidity over a month.

Thermal and electrical treatments induce morphology and performance changes.

Standard procedures for other 2D materials may not be suitable for black P devices.

Abstract

Atomic layers of black phosphorus (P) isolated from its layered bulk make a new two-dimensional (2D) semiconducting crystal with sizable direct bandgap, high carrier mobility, and promises for 2D electronics and optoelectronics. However, the integrity of black P crystal could be susceptible to a number of environmental variables and processes, resulting in degradation in device performance even before the device optical image suggests so. Here, we perform a systematic study of the environmental effects on black P electronic devices through continued measurements over a month under a number of controlled conditions, including ambient light, air, and humidity, and identify evolution of device performance under each condition. We further examine effects of thermal and electrical treatments on inducing morphology and, performance changes and failure modes in black P devices. The results suggest that procedures well established for nanodevices in other 2D materials may not directly apply to black P devices, and improved procedures need to be devised to attain stable device operation.