Giubileo Filippo, Faella Enver, Capista Daniele, Passacantando Maurizio, Durante Ofelia, Kumar Arun, Pelella Aniello, Intonti Kimberly, Viscardi Loredana, De Stefano Sebastiano, Martucciello Nadia, Craciun Monica F, Russo Saverio, Di Bartolomeo Antonio
CNR-SPIN Salerno, via Giovanni Paolo II n.132, 84084 Fisciano, Italy.
Department of Physical and Chemical Science, University of L'Aquila, Via Vetoio, Coppito, 67100 L'Aquila, Italy.
Nanoscale. 2024 Sep 12;16(35):16718-16728. doi: 10.1039/d4nr02109f.
The field emission properties of rhenium diselenide (ReSe) nanosheets on Si/SiO substrates, obtained through mechanical exfoliation, have been investigated. The n-type conduction was confirmed by using nano-manipulated tungsten probes inside a scanning electrode microscope to directly contact the ReSe flake in back-gated field effect transistor configuration, avoiding any lithographic process. By performing a finite element electrostatic simulation of the electric field, it is demonstrated that the use of a tungsten probe as anode, at a controlled distance from the ReSe emitter surface, allows the collection of emitted electrons from a reduced area that furtherly decreases by reducing the tip-sample distance, allowing a local characterization of the field emission properties. Experimentally, it is shown that the turn-on voltage can be linearly reduced by reducing the cathode-anode separation distance. By comparing the measured current-voltage characteristics with the numerical simulations, it is also shown that the effective field enhancement on the emitter surface is larger than expected because of surface defects. Finally, it is confirmed that ReSe nanosheets are suitable field emitters with high time stability and low current fluctuations.
对通过机械剥离法在硅/二氧化硅衬底上获得的二硒化铼（ReSe）纳米片的场发射特性进行了研究。通过在扫描电极显微镜内使用纳米操纵钨探针，以背栅场效应晶体管配置直接接触ReSe薄片，避免任何光刻工艺，从而证实了n型传导。通过对电场进行有限元静电模拟，结果表明，在距ReSe发射极表面可控距离处使用钨探针作为阳极，能够从减小的区域收集发射电子，通过减小尖端与样品的距离，该区域会进一步减小，从而实现场发射特性的局部表征。实验表明，通过减小阴极与阳极的分离距离，可以线性降低开启电压。通过将测量的电流-电压特性与数值模拟进行比较，还表明由于表面缺陷，发射极表面的有效场增强比预期的要大。最后，证实了ReSe纳米片是具有高时间稳定性和低电流波动的合适场发射体。
