Improved contact resistivity methods based on Cox-Strack and 4 point probe

Download
2021-6
Tsoi, Konstantin
Contact resistivity (c) of metal-semiconductor or conductive layer-semiconductor in the solar cells can limit their performance if not treated with care. It is, therefore, of great importance to be able to accurately measure rc for its optimization purposes. Many methodologies have been developed for this purpose. In this thesis, various methods for extracting rc are investigated. Namely, Transfer Length, Cox and Strack, four-point probe methods are discussed in detail. Cox and Strack and four-point probe methods are further extended with analytical formulations to simplify the fabrication of test samples and increase the speed of extracting rc. Good agreement (relative error < 10 % for extended Cox and Strack; < 1.9 % for extended four-point probe) between the derived analytical formulations for the proposed methods and finite element method simulations is achieved. Furthermore, c of experimentally fabricated test samples determined using classic and improved methodologies is reported with good agreement between the two. Finally, a simulation study is performed to determine the optimum dimensions of the front metal grid design to be utilized in the fabrication of the solar cells.

Suggestions

Efficient Light Trapping in Inverted Nanopyramid Thin Crystalline Silicon Membranes for Solar Cell Applications
MAVROKEFALOS, Anastassios; HAN, Sang Eon; Yerci, Selçuk; Branham, Matthew S.; CHEN, Gang (2012-06-01)
Thin-film crystalline silicon (c-Si) solar cells with light-trapping structures can enhance light absorption within the semiconductor absorber layer and reduce material usage. Here we demonstrate that an inverted nanopyramid light-trapping scheme for c-Si thin films, fabricated at wafer scale via a low-cost wet etching process, significantly enhances absorption within the c-Si layer. A broadband enhancement in absorptance that approaches the Yablo-novitch limit (Yablo-novitch, E. J. Opt. Soc. Am. 1987, 72, ...
New DPP and Selenophene based NIR Absorbing Polymers for Organic Solar Cell Applications
Günbaş, Emrullah Görkem; Toppare, Levent Kamil; Oklem, Gulce (2018-07-06)
The broad spectrum of sunlight which spans from 300 nm to 1200 nm cannot be effectively utilized in organic solar cells since most organic polymers have absorption between 300 ve 800 nm range. Recently coppolymers from diketopyrrolopyrrole (DPP) and simple donors such as thiophene and furan was shown to achieve absorption maxima around 800 nm. Here we shown that DPP coupled with selenophene pushes the absorption even futher and a polymer with absorption maxima at 830 nm (absorption onset 930 nm) could be at...
Designing heat exchanger with spatially variable surface area for passive cooling of PEM fuel cell
Ozden, Ender; Tolj, Ivan; Barbir, Frano (2013-03-01)
The purpose of this work was to design a heat exchanger for a Polymer Electrolyte Membrane (PEM) fuel cell, which would ensure such a temperature profile along the fuel cell cathode channel resulting in close to 100% relative humidity along the channel without external humidification. To achieve this, 3D numerical simulations of a single PEM fuel cell were performed using commercial Computational Fluid Dynamics (CFD) software (ANSYS Fluent). Based on the simulation results a variable surface area finned hea...
Maximizing the performance of single and multijunction MA and lead-free perovskite solar cell
Azadinia, M.; Ameri, Mohsen; Ghahrizjani, R.T.; Fathollahi, M. (2021-06-01)
Finding a highly stable and appropriate perovskite solar cell with optimum design parameters is crucial for being included as the top cell in tandem structure, with Si as the bottom cell, to realize the power conversion efficiencies (PCEs) over the limits imposed by Shockley-Queisser theory. Here, we quantize the performance of methylammonium (MA) and lead (Pb)-free all-inorganic cesium tin-germanium triiodide (CsSnxG1-xI3) by combining CsSnI3 (Eg = 1.31 eV) and CsGeI3 (Eg = 1.63 eV) perovskites for standal...
Optimization of laser processing for PERC type c-Si solar cells
Genç, Ezgi; Turan, Raşit; Department of Micro and Nanotechnology (2019)
Passivated Emitter Rear Contact (PERC) type solar cells, which currently owns a similar market share as the standard type solar cells, is expected to be the dominant type of the photovoltaic (PV) market in near future (ITRPV, 2019) due to its high performance/cost ratio. Hence, it is critical to optimize PERC process steps to achieve higher efficiencies. In PERC concept, the stack of a passivation layer and SiNx capping layer is locally ablated to form low recombination and low resistive contacts. In this w...
Citation Formats
K. Tsoi, “Improved contact resistivity methods based on Cox-Strack and 4 point probe,” M.S. - Master of Science, Middle East Technical University, 2021.