Zeptogram Level Mass Sensing of Light Weight Gas Molecules Using Graphene Nanomechanical (GNEM) Resonator
Zeptogram Level Mass Sensing of Light Weight Gas Molecules Using Graphene Nanomechanical (GNEM) Resonator
复制标题
DOI：
10.1109/icsens.2018.8589705
复制
发表时间：
2018-10
期刊：
影响因子：
--
通讯作者：
M. Muruganathan;H. Miyashita;Jothiramalingam Kulothungan;Marek E. Schmidt;H. Mizuta
中科院分区：
文献类型：
--
作者：
M. Muruganathan;H. Miyashita;Jothiramalingam Kulothungan;Marek E. Schmidt;H. Mizuta
在这项工作中，我们提出了利用顶部选通石墨烯谐振器对氢气和氩气混合气体进行泽波图能级质量传感。利用单层化学气相沉积石墨烯制备了长1µm、宽5 0 0 nm的谐振腔和用于射频测量的共平面波导。在腔内真空条件下，测得双固支石墨烯谐振器的谐振频率为95.5 MHz，与基于连续介质模型的理论计算结果一致。随着注入氢气和Ar混合气体的腔内压力的增加，谐振腔的谐振频率随腔内Q因子的降低而不断下移。这归因于谐振器上吸附的分子数量的增加。我们测量了当压强从5.6~6.2mathm{x}10^-3}$pA变化到6.2mathm{x}10^-3}$Pa时，~886 zeptogram的质量增加。基于范德华修正的第一性原理模拟，计算出石墨烯-Ar和H2分子的结合能分别为0.141和0.287 eV。这些测量和模拟结果清楚地表明了将石墨烯纳米机械谐振器用于轻质分子质谱仪的可能性。
In this work, we present zeptogram level mass sensing of Hydrogen and Argon mixture gas using top-gated graphene resonator. Monolayer chemical vapor deposition graphene was used to fabricate $1\mu\mathrm{m}$ length and 500 nm width resonator along with co-planner waveguide for RF measurements. The resonant frequency of doubly clamped graphene resonator was measured to be 95.5 MHz in the vacuum condition of the chamber, which is consistent with the theoretical calculation based on continuum model. With the increase in the chamber pressure by injecting Hydrogen and Argon mixture gas, the resonant frequency of the resonator down shifted continuously along with the resonator Q factor degradation. This is attributed to the increase in the number adsorped molecules onto the resonator. We measured the increase in mass of ~886 zeptogram when the pressure level is changed from $5.6\mathrm{x}10^{-3}$ Pa to $6.2\mathrm{x}10^{-3}$ Pa. Binding energy of graphene-Ar and H2 molecules was calculated to be 0.141 and 0.287 eV, respectively, based on the first-principles simulation with van der Waals (vdW) correction. These measurement and simulation results clearly indicate the possibility of using graphene nanomechanical resonator for light weight molecules mass spectrometry applications.