Contact resistance

About: Contact resistance is a research topic. Over the lifetime, 15262 publications have been published within this topic receiving 232144 citations. The topic is also known as: electrical contact resistance & ECR.

Microscopic and macroscopic thermal contact resistances of pressed mechanical contacts

Abstract: Contact heat transfer at mechanical pressed contacts between two materials is very important in many applications. There are two types of thermal contact resistance at the interface of two solids. One of them is due to the constriction of heat flow lines at the interface, commonly known as thermal contact resistance, and the engineering literature has extensively dealt with this macroscopic phenomenon. The other type of constriction resistance is instead microscopic in nature. If the characteristic dimension of the constriction becomes comparable to the mean free path of the heat carriers (i.e., electrons and phonons), then there is a ballistic component to the constriction resistance. For different materials on the two sides, thermal boundary resistance due to phonon acoustic mismatch and to electron-phonon interaction in the case of metals becomes important. Here a unified model is developed which bridges the gap between the macroscopic constriction resistance and the microscopic contact resistance for ...

Contact Engineering High-Performance n-Type MoTe2 Transistors.

Abstract: Semiconducting MoTe2 is one of the few two-dimensional (2D) materials with a moderate band gap, similar to silicon. However, this material remains underexplored for 2D electronics due to ambient instability and predominantly p-type Fermi level pinning at contacts. Here, we demonstrate unipolar n-type MoTe2 transistors with the highest performance to date, including high saturation current (>400 μA/μm at 80 K and >200 μA/μm at 300 K) and relatively low contact resistance (1.2 to 2 kΩ·μm from 80 to 300 K), achieved with Ag contacts and AlOx encapsulation. We also investigate other contact metals (Sc, Ti, Cr, Au, Ni, Pt), extracting their Schottky barrier heights using an analytic subthreshold model. High-resolution X-ray photoelectron spectroscopy reveals that interfacial metal-Te compounds dominate the contact resistance. Among the metals studied, Sc has the lowest work function but is the most reactive, which we counter by inserting monolayer hexagonal boron nitride between MoTe2 and Sc. These metal-insulator-semiconductor (MIS) contacts partly depin the metal Fermi level and lead to the smallest Schottky barrier for electron injection. Overall, this work improves our understanding of n-type contacts to 2D materials, an important advance for low-power electronics.

Enhanced back reflectance and quantum efficiency in Cu(In,Ga)Se2 thin film solar cells with a ZrN back reflector

Abstract: A reactively sputtered ZrN reflector layer on top of the conventional Mo back contact yields enhanced absorber/back contact reflectance in Cu(In,Ga)Se2 thin film solar cells. Improved long wavelength quantum efficiency is demonstrated with a ZrN reflector at a Cu(In,Ga)Se2 thickness of 0.5 μm. The optical gain with respect to a standard Mo back contact is initially offset by increased back contact recombination and contact resistance, but these electronic losses can be suppressed by Ga grading of the absorber or by inclusion of a contact layer of MoSe2. This allows for a significantly improved power conversion efficiency of devices with sub-micron Cu(In,Ga)Se2 thickness.