| AVS 64th International Symposium & Exhibition | |
| 2D Materials Focus Topic | Thursday Sessions |
| Session 2D-ThP |
| Session: | 2D Materials Poster Session |
| Presenter: | Alireza Fali, Georgia State University |
| Authors: | S. Gamage, Georgia State University A. Fali, Georgia State University N. Aghamiri, Georgia State University L. Yang, Purdue University P.D. Ye, Purdue University Y. Abate, Georgia State University |
| Correspondent: | Click to Email |
Topic:2D materials
Black phosphorus (BP) possesses several extraordinary properties such as layered structure but with a unique puckered single-layer geometry, thickness dependent direct bandgap, high carrier mobility and anisotropic in-plane properties that not shared by other exfoliable materials that are highly desirable from the point of view of fundamental science and modern optoelectronics applications. The excitement about this material has always been accompanied by unreserved skepticism due to its extraordinary degradation under ambient conditions. Here we show ambient degradation of exfoliated BP can be effectively suppressed using thin layer of hybrid MOCVD coating of BN followed by ALD coating of Al2O3. We have extensively studied the time dependent surface, optical and electrical properties of BP encapsulated by BN and/or Al2O3 using nanoscale infrared imaging and I-V characterizations. Our results show hybrid thin layer (~5 nm) BN/Al2O2 coated BP exfoliated on SiO2 substrate is protected from degradation in ambient for over 45 days much longer than those coated on BN or Al2O3 layers only as well as those exfoliated on Si substrate. Our theoretical modeling of the experimental degradation growth pattern shows that the influence of neighboring elements on the degradation of a given element is minimal for BP flakes with hybrid coating. Electrical characterization further confirms the effectiveness of BN/Al2O3 as encapsulation layer and gate dielectrics with minor changes after several weeks.