Publication Date:
2015-09-22
Description:
Metal-semiconductor Schottky junction devices composed of chemical vapor deposition grown monolayer graphene on p -type silicon substrates are fabricated and characterized. Important diode parameters, such as the Schottky barrier height, ideality factor, and series resistance, are extracted from forward bias current-voltage characteristics using a previously established method modified to take into account the interfacial native oxide layer present at the graphene/silicon junction. It is found that the ideality factor can be substantially increased by the presence of the interfacial oxide layer. Furthermore, low frequency noise of graphene/silicon Schottky junctions under both forward and reverse bias is characterized. The noise is found to be 1/ f dominated and the shot noise contribution is found to be negligible. The dependence of the 1/ f noise on the forward and reverse current is also investigated. Finally, the photoresponse of graphene/silicon Schottky junctions is studied. The devices exhibit a peak responsivity of around 0.13 A/W and an external quantum efficiency higher than 25%. From the photoresponse and noise measurements, the bandwidth is extracted to be ∼1 kHz and the normalized detectivity is calculated to be 1.2 × 10 9 cm Hz 1/2 W −1 . These results provide important insights for the future integration of graphene with silicon device technology.
Print ISSN:
0021-8979
Electronic ISSN:
1089-7550
Topics:
Physics
