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.

Towards an optimal contact metal for CNTFETs

Abstract: Downscaling of the contact length Lc of a side-contacted carbon nanotube field-effect transistor (CNTFET) is challenging because of the rapidly increasing contact resistance as Lc falls below 20–50 nm. If in agreement with existing experimental results, theoretical work might answer the question, which metals yield the lowest CNT–metal contact resistance and what physical mechanisms govern the geometry dependence of the contact resistance. However, at the scale of 10 nm, parameter-free models of electron transport become computationally prohibitively expensive. In our work we used a dedicated combination of the Green function formalism and density functional theory to perform an overall ab initio simulation of extended CNT–metal contacts of an arbitrary length (including infinite), a previously not achievable level of simulations. We provide a systematic and comprehensive discussion of metal–CNT contact properties as a function of the metal type and the contact length. We have found and been able to explain very uncommon relations between chemical, physical and electrical properties observed in CNT–metal contacts. The calculated electrical characteristics are in reasonable quantitative agreement and exhibit similar trends as the latest experimental data in terms of: (i) contact resistance for Lc = ∞, (ii) scaling of contact resistance Rc(Lc); (iii) metal-defined polarity of a CNTFET. Our results can guide technology development and contact material selection for downscaling the length of side-contacts below 10 nm.

The Next Frontier: Electrodeposition for Solar Cell Fabrication

Abstract: Electrodeposition for solar cells is an active area of research and it has been shown to provide improved benefits in several solar technologies. For the silicon solar cell contacts, electrodeposited metal contacts result in 1-2% solar cell efficiency improvement due to a lower processing temperature with better yield than screen printing, improved contact resistance, lower overall resistance, and the ability to fabricate smaller contacts that reflect less sunlight. This film electrodeposited chalcopyrite and kesterite offer very low-cost manufacturing. They can be used with rigid glass or flexible metallic substrates potentially opening up new applications for solar energy.

Silver Nanowire Transparent Conductive Electrodes for High-Efficiency III-Nitride Light-Emitting Diodes

Abstract: Silver nanowires (AgNWs) have been successfully demonstrated to function as next-generation transparent conductive electrodes (TCEs) in organic semiconductor devices owing to their figures of merit, including high optical transmittance, low sheet resistance, flexibility, and low-cost processing In this article, high-quality, solution-processed AgNWs with an excellent optical transmittance of 965% at 450 nm and a low sheet resistance of 117 Ω/sq were demonstrated as TCEs in inorganic III-nitride LEDs The transmission line model applied to the AgNW contact to p-GaN showed that near ohmic contact with a specific contact resistance of ~10(-3) Ωcm(2) was obtained The contact resistance had a strong bias-voltage (or current-density) dependence: namely, field-enhanced ohmic contact LEDs fabricated with AgNW electrodes exhibited a 56% reduction in series resistance, 565% brighter output power, a 675% reduction in efficiency droop, and a approximately 30% longer current spreading length compared to LEDs fabricated with reference TCEs In addition to the cost reduction, the observed improvements in device performance suggest that the AgNWs are promising for application as next-generation TCEs, to realise brighter, larger-area, cost-competitive inorganic III-nitride light emitters

Thickness-dependent electron mobility of single and few-layer MoS2 thin-film transistors

Abstract: We investigated the dependence of electron mobility on the thickness of MoS2 nanosheets by fabricating bottom-gate single and few-layer MoS2 thin-film transistors with SiO2 gate dielectrics and Au electrodes. All the fabricated MoS2 transistors showed on/off-current ratio of ∼107 and saturated output characteristics without high-k capping layers. As the MoS2 thickness increased from 1 to 6 layers, the field-effect mobility of the fabricated MoS2 transistors increased from ∼10 to ∼18 cm2V−1s−1. The increased subthreshold swing of the fabricated transistors with MoS2 thickness suggests that the increase of MoS2 mobility with thickness may be related to the dependence of the contact resistance and the dielectric constant of MoS2 layer on its thickness.