Alleviation of fermi-level pinning effect at metal/germanium interface by the insertion of graphene layers

作者：Baek Seung heon Chris; Seo Yu Jin; Oh Joong Gun; Park Min Gyu Albert; Bong Jae Hoon; Yoon Seong Jun; Seo Minsu; Park Seung young; Park Byong Guk; Lee Seok Hee^*

来源：Applied Physics Letters, 2014, 105(7): 073508.

DOI：10.1063/1.4893668

In this paper, we report the alleviation of the Fermi-level pinning on metal/n-germanium (Ge) contact by the insertion of multiple layers of single-layer graphene (SLG) at the metal/n-Ge interface. A decrease in the Schottky barrier height with an increase in the number of inserted SLG layers was observed, which supports the contention that Fermi-level pinning at metal/n-Ge contact originates from the metal-induced gap states at the metal/n-Ge interface. The modulation of Schottky barrier height by varying the number of inserted SLG layers (m) can bring about the use of Ge as the next-generation complementary metal-oxide-semiconductor material. Furthermore, the inserted SLG layers can be used as the tunnel barrier for spin injection into Ge substrate for spin-based transistors.

• 出版日期2014-8-18