Related Experiment Video
Updated: Oct 23, 2025
Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
Surface Ohmic Conductivity on a Mott Insulator Based on a One-dimensional Bromide-bridged Nickel(III) Complex
Masanori Wakizaka1, Hiroaki Iguchi1, Shinya Takaishi1
1Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-Ku, Sendai, 980-8578, Japan.
Abstract:
Ohmic contacts are of critical importance to improve the performance of semiconductor devices as well as those of low-dimensional materials. Halogen-bridged metal complexes (MX-Chains) are fascinating quasi-one-dimensional (1D) electronic materials. However, reports on the electrical characteristics of MX-Chains remain elusive. Herein, we report the electrical characteristics of single crystals of [Ni(chxn)2 Br]Br2 (chxn: (1R,2R)-(-)-1,2-cyclohexanediamine), which is a 1D Mott insulator, using different probe arrangements. [Ni(chxn)2 Br]Br2 was shown for the first time to exhibit Ohmic characteristics on the crystal surface, albeit that the conductivity behavior of the interior of the crystal is nonlinear due to the Joule heating effect. The current flow on the surface is shallow (a few micrometers in depth) despite the millimeter-scale crystal size; this phenomenon is strongly connected to its structural anisotropy. The Ohmic contact revealed in this work should be valuable for the application of MX-Chains as electronic devices in the near future.
Related Concept Videos
01:24Metal-Semiconductor Junctions
Schottky Barriers
Schottky barriers arise when a metal with a work function (Φm) contacts a semiconductor with a different work function (Φs). Initially, electrons transfer until the Fermi levels of the metal and semiconductor align at equilibrium. For instance, if Φm > Φs, the semiconductor Fermi level is higher than the metal's before contact. The...
02:42Valence Bond Theory
02:34Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:35Band Theory
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...
01:22Semiconductors
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...