Effect of graphene tunnel barrier on Schottky barrier height of Heusler alloy Co_2MnSi/graphene/n-Ge

• 作 者: 李桂芳 胡晶 吕辉 崔智军 候晓伟 刘诗斌 杜永乾
• 机 构: School of Electronics and Information, Northwestern Polytechnical University,
• 出 处: Chinese Physics B
• 发表日期: 2016年02期
• 关键词: Schottky junction tunnel insertion tunneling modulated Fermi symmetric Richardso

We demonstrate that the insertion of a graphene tunnel barrier between Heusler alloy Co_2MnSi and the germanium(Ge) channel modulates the Schottky barrier height and the resistance–area product of the spin diode. We confirm that the Fermi level is depinned and a reduction in the electron Schottky barrier height(SBH) occurs following the insertion of the graphene layer between Co_2MnSi and Ge. The electron SBH is modulated in the 0.34 eV–0.61 eV range. Furthermore,the transport mechanism changes from rectifying to symmetric tunneling following the insertion. This behavior provides a pathway for highly efficient spin injection from a Heusler alloy into a Ge channel with high electron and hole mobility.

We demonstrate that the insertion of a graphene tunnel barrier between Heusler alloy Co_2MnSi and the germanium (Ge) channel modulates the Schottky barrier height and the resistance-area product of the spin diode. We confirm that the Fermi level is depinned and a reduction in the The electron SBH is below the insertion of the graphene layer between Co_2MnSi and Ge. The electron SBH is modulated in the 0.34 eV-0.61 eV range. Furthermore, the transport mechanism changes from rectifying to symmetrical tunneling following the insertion. behavior provides a pathway for highly efficient spin injection from a Heusler alloy into a Ge channel with high electron and hole mobility.