I. Introduction
In recent times, atomically thin 2-D materials are being extensively explored as an alternative channel material for transistor technologies able to meet Moore’s law projections in the long-term future. Most of these materials, e.g., graphene, hBN, phosphorene, transition metal dichalcogenides (TMD), such as MoS2, WS2, MoSe2, WSe2, MoTe2, and so on [1]–[9], are naturally available in layered form, where 2-D platelets are weakly bonded by van der Waals forces to form 3-D crystals. In an alternate route, recent efforts are also observed to extract 2-D analogues from conventional bulk semiconductors, such as Si, Ge, and GaN [10]–[15]. Among these materials, germanane, a hydrogenated monolayer of germanium, has attracted much attention. Unlike TMDs, which show higher bandgap and higher effective mass, Germanane inherits a very interesting property of having low effective mass along with a relatively high bandgap [15]. From recent first principle-based assessments [16], it was further concluded that chair morphology of Germanane has better potential for conventional and tunnel FET applications than its boat morphology. Stable structure of Germanane has been reported for the first time in 2013 [15], and later used for fabrication of Schottky diodes and FETs [17]–[19].