High-performance CdS nanobelt field-effect transistors with high-κ HfO2 top-gate dielectrics

Abstract

We have fabricated high-performance enhancement and depletion mode (E-and D-mode) top-gate metal-insulator-semiconductor field-effect transistors (T-G MISFETs) using two kinds of CdS nanobelts (NBs), labeled as NB A and NB B, respectively. High-k HfO 2 dielectric is used as the insulator layer. The thicknesses of NBs A and B are about 60 and 180 nm, respectively. The threshold voltage and subthreshold swing of the CdS NB A T-G MISFET are about 0.15 V and 62 mV/dec, respectively. The on/off ratio is about 6 Â 10 4 , which is the best result for E-mode CdS nanoFETs reported so far. The threshold voltage, on/off ratio and peak transconductance of the CdS NW B T-G MISFET are about À3.4 V, 2 Â 10 9 , and 11 mS, respectively. The on/off ratio, to the best of our knowledge, is the highest reported for nanoFETs so far. Both of the two kinds of T-G MISFETs have quite small hysteresis in their transfer characteristics. The mechanisms for the different gate transfer characteristics are discussed. Corresponding Si back-gate CdS NB MISFETs each with a 600 nm SiO 2 film as the insulator layer are also measured for comparison.

Template-free synthesis of CdS hollow nanospheres based on an ionic liquid assisted hydrothermal process and their application in photocatalysis

“…In particular, CdS, as an important semiconductor of II-VI group with a band gap at 2.42 eV at 300 K, is of great interest due to its important applications as nanoelectronic and optoelectronic materials [10][11][12][13]. Since the material properties mainly depend on the morphological features, a variety of CdS nanostructures have been synthesized, including nanowires [10], nanoribbons [11], nanobelts [12] and hierarchical dendrites [13]. Many efforts have been devoted to the synthesis of CdS hollow micro-and nanostructures.…”

Facile method to prepare CdS nanostructure based on the CdTe films

“…Since the chemical vapor deposition method is known to be effective in the large-scale fabrication of CdS nanostructures, Wu et al [28] prepared CdS nanobelts using this method. In the preparing process, the Si wafer coated gold (Au) film is used as the substrate and its growth temperature is as high as 800 o C. Au film is a vital factor in their experiments, which promote formation and growth of CdS nanobelts.…”

Crystallization of II-VI semiconductor compounds forming long microcrystalline linear assemblies

“…Other types of nanostructures such as nanowires, nanobelts, nanorods, etc. based on these materials, mainly CdS, have also been reported [11][12][13][14] . Furthermore, these nanostructures with novel physical and chemical properties have found applications in devices such as solar cells and thin film transistors (TFTs) at the nanoscale level 11,14 .…”

“…based on these materials, mainly CdS, have also been reported [11][12][13][14] . Furthermore, these nanostructures with novel physical and chemical properties have found applications in devices such as solar cells and thin film transistors (TFTs) at the nanoscale level 11,14 . Therefore, the understanding of the growth mechanisms of nanostructures and self-assembled structures of CdS and CdTe is of major relevance to extend the potential applications of these semiconductors to the nanoscale level.…”