Open AccessP ‐doping decrease and mobility increase of graphene in atmosphere
Author(s) -
Zhang Qingwei,
Li Ping,
Wang Gang
Publication year - 2017
Publication title -
micro and nano letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.25
H-Index - 31
ISSN - 1750-0443
DOI - 10.1049/mnl.2016.0556
Subject(s) - graphene , materials science , electron mobility , doping , oxide , thin film , nanotechnology , condensed matter physics , optoelectronics , metallurgy , physics
An approach to decrease the P ‐doping density of graphene and increase the mobility of graphene field‐effect transistors (GFETs) is reported. With a layer of natural aluminium oxide (natural‐AlO x ) thin film covered on the surface of graphene, the Dirac point voltage of the GFETs decreases 25 V while it experiences the mobility increase of 42 cm 2 /(V s) after exposure in the atmosphere for 1 month. To understand this phenomenon, other two situations are researched, the Dirac point voltage of the identical GFETs with no thin film on graphene increases more than 15 V and its mobility decreases 90 cm 2 /(V s) after 1 month. The last situation is that the Dirac point voltage and the mobility have no significant changes with an AlO x deposited by electron beam evaporation (Al 2 O 3 ‐EBE) on graphene. These phenomena indicate that the natural‐AlO x thin film is capable of reducing p ‐type impurities on the graphene and bringing the better reliability to the GFETs.