Graphene enhanced field emission from InP nanocrystals

Abstract

We report the observation of field emission (FE) from InP nanocrystals (NCs) epitaxially grown on an array of p-Si nanotips. We prove that FE can be enhanced by covering the InP NCs with graphene. The measurements are performed inside a scanning electron microscope chamber with a nano-controlled W-thread used as an anode. We analyze the FE by Fowler-Nordheim theory and find that the field enhancement factor increases monotonically with the spacing between the anode and the cathode. We also show that InP/p-Si junction has a rectifying behavior, while graphene on InP creates an ohmic contact. Understanding the fundamentals of such nanojunctions is key for applications in nanoelectronics.

Effect of Electron Irradiation on the Transport and Field Emission Properties of Few-Layer MoS2 Field-Effect Transistors

“…[42][43][44][45] We remark that the FE curves typically show large instabilities (fluctuations and drops) due to the presence and desorption of adsorbates (on the emitting surface), which act as nanoprotrusions with higher field enhancement factor and can be evaporated by Joule heating for the high FE currents. [46,47] Consequently, as standard procedure, we always perform an electric conditioning by repeating several successive voltage sweeps (not reported here) to stabilize the emitting surface. All reported data in the following have been measured after proper electric conditioning.…”

Contact resistance and mobility in back-gate graphene transistors

“…Graphene is commonly produced by exfoliation from graphite [28,29], epitaxial growth on SiC [30] or chemical vapor deposition (CVD) [31,32]. In particular, CVD produces uniform and large-scale graphene flakes of high-quality and is compatible with the silicon technology; therefore, it has been largely exploited to realize new electronic devices such as diodes [33][34][35][36], transistors [37][38][39], field emitters [40,41], chemical-biological sensors [42,43], optoelectronic systems [44], photodetectors [45][46][47][48][49][50] and solar cells [51].…”

Nanotip Contacts for Electric Transport and Field Emission Characterization of Ultrathin MoS2 Flakes

“…For a flat cathode, FE is enabled by a strong electric field (several kV/µm), while if the cathode surface has sharp edges or protrusions, electrons may be extracted by a considerably lower applied electric field, since the physical geometry provides a field enhancement near the emitting surface. To date, several nanostructures have been investigated as possible field emitters, like metallic nanowires and nanoparticles [26][27][28], semiconducting nanowires and nanoparticles [29][30][31][32][33], nanodiamonds [34], carbon nanostructures [35], carbon nanotubes (CNTs) [36][37][38][39][40][41], and graphene [33,[42][43][44]. Instead, few studies have investigated FE from MoS 2 structures, such as sheets and nanosheets [45,46], nanotubes and nanoflowers [47,48], nanostructures [49], thin films [50], and bilayers [12].…”