We study the effects of low-energy electron beam irradiation up to 10 keV ongraphene based field effect transistors. We fabricate metallic bilayerelectrodes to contact mono- and bi-layer graphene flakes on SiO$_2$, obtainingspecific contact resistivity $\rho_c \simeq 19 k\Omega \mu m^2$ and carriermobility as high as 4000 cm$^2$V$^{-1}$s$^{-1}$. By using a highly dopedp-Si/SiO$_2$ substrate as back gate, we analyze the transport properties of thedevice and the dependence on the pressure and on the electron bombardment. Wedemonstrate that low energy irradiation is detrimental on the transistorcurrent capability, resulting in an increase of the contact resistance and areduction of the carrier mobility even at electron doses as low as 30$e^-/nm^2$. We also show that the irradiated devices recover by returning totheir pristine state after few repeated electrical measurements.
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机译：我们研究了高达10 keV的低能量电子束辐照基于石墨烯的场效应晶体管。我们制造了金属双层电极以在SiO $ _2 $上接触单层和双层石墨烯薄片，获得了比接触电阻率$ \ rho_c \ simeq 19 k \ Omega \ mu m ^ 2 $，载流子迁移率高达4000 cm $ ^ 2 $ V $ ^ {-1} $ s $ ^ {-1} $。通过使用高度掺杂的p-Si / SiO $ _2 $衬底作为背栅，我们分析了器件的传输特性以及对压力和电子轰击的依赖性。 Wed证明了低能量辐照对晶体管的电流能力是有害的，即使在电子剂量低至30 $ e- / nm ^ 2 $的情况下，也会导致接触电阻的增加和载流子迁移率的降低。我们还表明，经过几次重复的电测量后，受辐照的设备会恢复到其原始状态，从而得以恢复。
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