posted on 2019-06-25, 00:00authored byYoung Jin Choi, Seongchan Kim, Hwi Je Woo, Young Jae Song, Yoonmyung Lee, Moon Sung Kang, Jeong Ho Cho
This paper introduces a strategy
to modulate a Schottky barrier formed at a graphene–semiconductor
heterojunction. The modulation is performed by controlling the work
function of graphene from a gate that is placed laterally away from
the graphene–semiconductor junction, which we refer to as the
remote gating of a Schottky barrier. The remote gating relies on the
sensitive work function of graphene, whose local variation induced
by locally applied field effect affects the change in the work function
of the entire material. Using Kelvin probe force microscopy analysis,
we directly visualize how this local variation in the work function
propagates through graphene. These properties of graphene are exploited
to assemble remote-gated vertical Schottky barrier transistors (v-SBTs)
in an unconventional device architecture. Furthermore, a vertical
complementary circuit is fabricated by simply stacking two remote-gated
v-SBTs (pentacene layer as the p-channel and indium gallium zinc oxide
layer as the n-channel) vertically. We consider that the remote gating
of graphene and the associated device architecture presented herein
facilitate the extendibility of graphene-based v-SBTs in the vertical
assembly of logic circuits.