Passivation of Germanium by Graphene for Stable Graphene/Germanium Heterostructure Devices

Journal Article · Tue Jun 25 00:00:00 EDT 2019 · ACS Applied Nano Materials

DOI:https://doi.org/10.1021/acsanm.9b00766· OSTI ID:1594848

Jacobberger, Robert M. ^[1]; Dodd, Matthew J. ^[2]; Zamiri, Marziyeh ^[2]; Way, Austin J. ^[2]; Arnold, Michael S. ^[2]; Lagally, Max G. ^[2]

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1. Univ. of Wisconsin, Madison, WI (United States); University of Wisconsin-Madison
2. Univ. of Wisconsin, Madison, WI (United States)

The scalable integration of graphene onto semiconductor platforms is an important step towards utilizing the exceptional structural, electronic, thermal, and mechanical properties of graphene in state-of-the-art technologies. Specifically, graphene films grown on Ge are an exciting materials system for high-performance electronics; however, the device performance depends sensitively on the structural, electronic, and chemical nature of the graphene/Ge interface. We have recently discovered that graphene grown directly on Ge via chemical vapor deposition (CVD) can passivate the Ge surface, preventing its oxidation for months—longer than alternate passivation methods reported in the literature. Yet, the factors that govern passivation are not understood. Here, we elucidate how the CVD growth conditions and Ge surface orientation affect Ge oxidation below graphene. We find that growing graphene with a high H2:CH4 flux ratio minimizes formation of defects in graphene, enhancing Ge passivation. While minimizing defects is important, surprisingly, we find that passivation depends much stronger on the Ge surface orientation. These results provide a route for the integration of graphene films with a pristine graphene/substrate interface on Ge, an important step towards stabilizing the Ge surface and realizing graphene-based or hybrid graphene/Ge heterostructure devices integrated directly on conventional semiconductor wafers.

• Research Organization: Univ. of Wisconsin, Madison, WI (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: FG02-03ER46028; SC0016007
• OSTI ID: 1594848
• Journal Information: ACS Applied Nano Materials, Journal Name: ACS Applied Nano Materials Journal Issue: 7 Vol. 2; ISSN 2574-0970
• Publisher: American Chemical Society (ACS)
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
Raman spectroscopy
X-ray photoelectron spectroscopy
chemical vapor deposition
defects
oxidation
pinholes