Layer-by-layer thinning without structural damage is essential for integrating two-dimensional materials (such as black phosphorus (BP)) in nanoelectronics, because their properties are primarily thickness-dependent. Unfortunately, most known etching processes for black phosphorus carry the possibility of structural degradation due to ion bombardment and thermal attack. In this study, we report a mild chemical thinning method free from causing physical damage, performed by modifying the sample configuration in a conventional reactive ion etching system. The thickness of mechanically exfoliated BP flakes can be easily controlled by modified plasma treatment, and these flakes maintain perfect crystallinity. Field-effect transistors based on thickness-controlled BP showed improved device performance after ion bombardment-free plasma etching. Our work provides a new way to realize the full potential of BP-based electronic devices.
Bibliographical noteFunding Information:
The research at Korea University was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2015R1D1A1A09057970). G. H. L. was supported by the Basic Science Research Program (2014R1A1A1004632) through NRF funded by the Ministry of Science, ICT & Future and the Human Resources Program in Energy Technology of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and was granted financial resource from the Ministry of Trade, Industry & Energy (No. 20154010200810).
© The Royal Society of Chemistry 2016.
All Science Journal Classification (ASJC) codes
- Materials Chemistry