MRS Meetings and Events

 

NM07.09.06 2022 MRS Fall Meeting

Nucleation of Hexagonal Germanium Grains on Defect Engineered MoS2 Monolayers

When and Where

Dec 1, 2022
9:30am - 9:45am

Hynes, Level 2, Room 203

Presenter

Co-Author(s)

Xuejing Wang1,Ryan Kaufmann2,Renjie Chen3,Towfiq Ahmed4,Michael Pettes1,Paul Kotula5,Ismail Bilgin6,Swastik Kar7,Jinkyoung Yoo1

Los Alamos National Laboratory1,The University of British Columbia2,University of California San Diego3,Pacific Northwest National Laboratory4,Sandia National Laboratories5,Ludwig-Maximilians-Universität München6,Northeastern University7

Abstract

Xuejing Wang1,Ryan Kaufmann2,Renjie Chen3,Towfiq Ahmed4,Michael Pettes1,Paul Kotula5,Ismail Bilgin6,Swastik Kar7,Jinkyoung Yoo1

Los Alamos National Laboratory1,The University of British Columbia2,University of California San Diego3,Pacific Northwest National Laboratory4,Sandia National Laboratories5,Ludwig-Maximilians-Universität München6,Northeastern University7
Hexagonal group IV semiconductors have shown great potential for optoelectronic devices as they possess direct electronic band gaps. However, challenges exist in reliable synthesis, which has been majorly limited to structural transfer in order to maintain the hexagonal in-plane lattices. In this work, we demonstrate the formation of hexagonal germanium (Ge) using molybdenum disulfide (MoS<sub>2</sub>) monolayer substrates. Suggested by quantum molecular dynamics calculation, the hexagonal Ge is thermodynamically preferrable to cubic Ge on monolayer MoS<sub>2</sub> with sulfur vacancies in certain temperature ranges, which is verified experimentally by transmission electron microscopy analyses. Structural characterization and Raman measurements have revealed that strain at Ge grain boundaries can facilitate nucleation of hexagonal Ge phase. Our reported approach to nucleate hexagonal Ge paves the way to accomplishing continuous thin films of hexagonal group IV semiconductors. Moreover, this study provides understanding on the formation mechanisms of heterostructures composed of two-dimensional materials and conventional three-dimensional semiconductors.

Keywords

transmission electron microscopy (TEM) | van der Waals

Symposium Organizers

Jeehwan Kim, Massachusetts Institute of Technology
Sanghoon Bae, Washington University in Saint Louis
Deep Jariwala, University of Pennsylvania
Kyusang Lee, University of Virginia

Publishing Alliance

MRS publishes with Springer Nature