3 years ago

Vertically Stacked and Self-Encapsulated van der Waals Heterojunction Diodes Using Two-Dimensional Layered Semiconductors

Vertically Stacked and Self-Encapsulated van der Waals Heterojunction Diodes Using Two-Dimensional Layered Semiconductors
Zhihao Xu, Jinshui Miao, Weida Hu, Suoming Zhang, Zhixian Zhou, Qing Li, Chuan Wang, Arthur Bowman
van der Waals heterojunctions using 2D semiconducting materials could overcome the defect issues included by lattice mismatch in conventional epitaxially grown heterojunctions with bulk materials and could enable a much wider palette for choice of materials and more sophisticated device design. Such 2D heterojunction devices are of great interest for important functional devices such as diodes, bipolar junction transistors, light-emitting diodes, and photodetectors. In this paper, we demonstrate a truly vertical p–n heterojunction diode built from 2D semiconductors (MoS2 and BP) and compare its performance against conventional lateral 2D heterojunction devices (partially overlapped 2D heterostructures). Both vertical and lateral p–n heterostructure diodes exhibit a strong rectification ratio even with no gate voltage applied. More importantly, the results show that the vertical diode delivers 70 times higher current density under forward bias than a conventional lateral device design and the improved device performance can be attributed to the complete elimination of series resistance. Low-temperature measurements and TCAD simulations are used to determine the barrier height at the junctions. Moreover, the vertical device structure allows certain ambiently unstable 2D semiconductors to be fully encapsulated by the materials on top, preventing the material from degradation. This work demonstrates the potential of using the vertically stacked 2D semiconductors for future nanoelectronic and optoelectronic devices with optimal performance.

Publisher URL: http://dx.doi.org/10.1021/acsnano.7b05755

DOI: 10.1021/acsnano.7b05755

You might also like
Never Miss Important Research

Researcher is an app designed by academics, for academics. Create a personalised feed in two minutes.
Choose from over 15,000 academics journals covering ten research areas then let Researcher deliver you papers tailored to your interests each day.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.