Transfer of graphene thin film obtained by PECVD method to Au/p-Si rectifier junction as interfacial layer and analysis of its barrier characteristics depending on sample temperature

It is well known that in metal–semiconductor rectifier junctions with an interface

layer, the drop potential across the interface layer modifies the barrier height by

changing the electric field in the semiconductor. Therefore, examining the barrier

characteristics of such structures depending on the sample temperature is

important in the development of novel devices. Based on this assumption, in

order to interpret the barrier characteristics of the Au/Graphene/p-Si/Al structure

in detail, its current–voltage (I–V) measurements were measured under dark

conditions in the temperature range of 120–320 K in 20 K steps. Graphene thin

film was grown on copper foil by plasma-enhanced chemical vapor deposition

(PECVD) method and then transferred as an interfacial layer on the clean and

polish surface of p-Si semiconductor base material made ohmic contact with

aluminum metal. After examining the morphological and optical properties of

the produced film, the gold metal was evaporated onto the film under vacuum

conditions to have a circular contact area of 1 mm diameter, as it is necessary for

electrical measurements. Various characteristic parameters such as ideality

factor, barrier height, saturation current, threshold voltage, rectifying ratio, and

series resistance of Au/Graphene/p-Si/Al structure were calculated from I–V

measurements taken depending on sample temperature using Rhoderick,

Norde, Cibils, and Chattopadhyay methods. The obtained results were interpreted

comparatively on the basis of Tung’s inhomogeneous barrier model.