A low Schottky barrier height and transport mechanism in gold–graphene–silicon (001) heterojunctions

Courtin Jules (1) , Sylvain Le Gall (2) , Pascal Chrétien (2) , Alain Moréac (1) , Gabriel Delhaye (1) , Bruno Lépine (1) , Sylvain Tricot (1) , Pascal Turban (1) , Philippe Schieffer (1) , Jean-Christophe Le Breton (1)

1 IPR - Institut de Physique de Rennes
2 GeePs - Laboratoire Génie électrique et électronique de Paris

The interface resistance at metal/semiconductor junctions has been a key issue for decades. The control of this resistance is dependent on the possibility to tune the Schottky barrier height. However, Fermi level pinning in these systems forbids a total control over interface resistance. The introduction of 2D crystals between semiconductor surfaces and metals may be an interesting route towards this goal. In this work, we study the influence of the introduction of a graphene monolayer between a metal and silicon on the Schottky barrier height. We used X-ray photoemission spectroscopy to rule out the presence of oxides at the interface, the absence of pinning of the Fermi level and the strong reduction of the Schottky barrier height. We then performed a multiscale transport analysis to determine the transport mechanism. The consistency in the measured barrier height at different scales confirms the good quality of our junctions and the role of graphene in the drastic reduction of the barrier height.

Domaines: Physique [physics]; Matière Condensée [cond-mat]

Courtin Jules, Sylvain Le Gall, Pascal Chrétien, Alain Moréac, Gabriel Delhaye, et al.. A low Schottky barrier height and transport mechanism in gold–graphene–silicon (001) heterojunctions. Nanoscale Advances, 2019, 1 (9), pp.3372-3378. ⟨10.1039/C9NA00393B⟩. ⟨hal-02284803⟩