Contact Resistance Measurements Research Articles

Turn-to-Turn Contact Resistance Measurement of NI REBCO Double Pancake Coils

Turn-to-Turn Contact Resistance Measurement of NI REBCO Double Pancake Coils

Innovating in-situ characterization: a comprehensive measurement system for measuring the ZT and the contact resistance of vertical thermolegs exploiting the vertical transfer length method

In order to optimize their system design and manufacturing processes, it is crucial to undertake a thorough electrical and thermal characterization of micro thermoelectric generators (µTEGs). To address this need, a highly advanced and fully integrated in-situ measurement system has been developed. The main objectives of this system are to (1) enable the measurement of ZT and thereby of all thermoelectric (TE) properties of thermolegs made from powder-based TE materials and (2) at the same time accurately measure the contact resistance between the TE material and the electrical contacts. The µTEG fabrication concept used in this study is based on copper-cladded printed circuit board (PCB) material as a substrate, using the Cu layers for easy contact formation. In a first step, an innovative measurement concept, based on a distinctive vertical rendition of the well-established transfer length method, has been realized, allowing for the in-situ measurement of contact resistance between the TE material and the copper conductors on the PCB substrate. This enables a comprehensive assessment of the impact exerted by the applied force and temperature during e.g. a hot-pressing step for compacting the powder-based thermolegs during the manufacturing process. In a second step, a comprehensive measurement platform, referred to as the ZT-Card, has been devised to facilitate the evaluation of all relevant TE material properties—Seebeck voltage, electrical conductivity and thermal conductivity (all measured in vertical cross-plane orientation)—inherent to a highly miniaturized thermoleg. Additionally, the ZT-Card also allows for the assessment of contact resistance between the copper contacts and the TE material. Successful testing of this measurement system inspires confidence in the capabilities of the platform and will aid in future µTEG development.

Corrosion resistance and conductivity behavior of Cr-Al-N MAX phase coatings prepared by magnetron sputtering technology

Chromium aluminum nitride (CrAlN) coatings containing Cr2AlN phase were prepared by unbalanced magnetron sputtering followed by annealing at 1000 °C. The crystal structures, X-ray diffraction patterns, and selected area electron diffraction patterns of the Cr2AlN phase were modeled using computer software and compared with experimental observations. A good agreement was found between the two sets of results, thereby confirming the presence of Cr2AlN phase in the coatings. While previous studies have demonstrated the formation of Cr2AlN phase theoretically, this study presents experimental evidence of its physical existence. The potentiodynamic polarization results and interfacial contact resistance measurements show that the CrAlN coating with Cr2AlN phase has excellent corrosion resistance (a corrosion current density of 5.35 × 10−7 A/cm2 and electrical conductivity of 5.5 mΩ·cm2) and is thus a promising candidate for the protection of fuel cell bipolar plates.

Comprehensive mechanical and tribological characterization of metal-polymer PTFE+Pb/Bronze coating by in-situ electrical contact resistance measurement augmented tribo-mechanical tests

This work thoroughly mechanically characterizes the DU® metal-polymer coating from GGB Bearing Technology by augmented multi-scale Instrumented Indentation Test (IIT). Nano-IIT will evaluate the uniformity of the Pb particles dispersion in the outermost layer. Dynamic nano-IIT will investigate the damping properties of the material as a function of load frequency. Micro-IIT will tackle the layer thickness evaluation and the gradient of mechanical properties through the layers by continuous multi-cycle indentations. Data augmentation provided by synchronous electric contact resistance (ECR) measurements will support the identification of the layer transitions. The coefficient of friction and the wear coefficient will also be obtained by linear reciprocating pin-on-disc testing with focus on the specific application to guide bushings for linear pneumatic actuators.

Optimizing Current Injection Technique for Enhancing Resistivity Method

Geo-electrical resistivity methods are widely used in various fields and have significant applications in scientific and practical research. Despite the widespread use of resistivity methods, current injection is a critical step in the process of resistivity methods, and the quality of current injection significantly impacts the accuracy of the resistivity measurements. One primary challenge is optimizing current injection techniques to enhance resistivity methods. The developed current injector model for the resistivity meter instrument enhances performance by increasing the voltage source to 400 Volts, extending measurement coverage. It provides three injection current options, 0.5A, 0.8A, and 1A, for efficient accumulator use, considering electrode distances and estimating earth resistance using Contact Resistance Measurement (CRM) to estimate the earth resistance. CRM mode ensures proper electrode connection before injection, thus improving measurement efficiency. The embedded TTGO LoRa ESP32 SX1276 facilitates wireless communication over 1.5 km, addressing challenges in remote and internet-limited areas. The model demonstrates reliability, validity, and durability in CRM mode and current injection measurement. Regarding reliability, we determine the relative error of the model by carrying out measurements repeatedly. In lab-scale testing, the average Relative Error in CRM mode is 0.65%, and in earth resistance measurement testing, it is 1.58%. These relative errors are below the 2% maximum error applied in the “Supersting”, a commercial resistivity instrument. The model's validity is defined by comparing the model with the measuring instrument; we have absolute error. In lab scale testing, the average Absolute Error in CRM mode is 3.08%, and in earth resistance measurement testing, it is 3.73%. The model's durability is tested by injecting current for a minute. After one minute of current injection, the power resistor component's temperature is stable at 30°C.

Optimizing Current Injection Technique for Enhancing Resistivity Method

Geo-electrical resistivity methods are widely used in various fields and have significant applications in scientific and practical research. Despite the widespread use of resistivity methods, current injection is a critical step in the process of resistivity methods, and the quality of current injection significantly impacts the accuracy of the resistivity measurements. One primary challenge is optimizing current injection techniques to enhance resistivity methods. The developed current injector model for the resistivity meter instrument enhances performance by increasing the voltage source to 400 Volts, extending measurement coverage. It provides three injection current options, 0.5A, 0.8A, and 1A, for efficient accumulator use, considering electrode distances and estimating earth resistance using Contact Resistance Measurement (CRM) to estimate the earth resistance. CRM mode ensures proper electrode connection before injection, thus improving measurement efficiency. The embedded TTGO LoRa ESP32 SX1276 facilitates wireless communication over 1.5 km, addressing challenges in remote and internet-limited areas. The model demonstrates reliability, validity, and durability in CRM mode and current injection measurement. Regarding reliability, we determine the relative error of the model by carrying out measurements repeatedly. In lab-scale testing, the average Relative Error in CRM mode is 0.65%, and in earth resistance measurement testing, it is 1.58%. These relative errors are below the 2% maximum error applied in the “Supersting”, a commercial resistivity instrument. The model's validity is defined by comparing the model with the measuring instrument; we have absolute error. In lab scale testing, the average Absolute Error in CRM mode is 3.08%, and in earth resistance measurement testing, it is 3.73%. The model's durability is tested by injecting current for a minute. After one minute of current injection, the power resistor component's temperature is stable at 30°C.

Thermal contact resistance measurement between EXG and polyimide substrates under varying pressure and thermal interfacial material

Thermal contact resistance measurement between EXG and polyimide substrates under varying pressure and thermal interfacial material

Plasma Electrolytically Surface-Engineered SS316L Bipolar Plates for PEM Fuel Cells

The proton exchange membrane fuel cell (PEMFC) technology is one of the clean energy technologies with advantages like, quick start-up, low working temperature (60-90 oC), high specific energy and specific power, and high reliability. Stainless steel bipolar plates for PEMFC offer many advantages over conventional graphite and graphite composites. Some of them have superior mechanical properties over graphite, the possibility to fabricate in thin cross sections, and easy formation of flow fields by stamping, which is more economical when compared with the grooving of the graphite counterparts. Despite these advantages, metallic bipolar plates are prone to corrosion in fuel cell working conditions which is often overcome by oxide layer formation on the surface. But the interfacial ohmic loss between the metallic bipolar plate and membrane electrode assembly due to oxide formation decreases the overall performance of PEMFC. For combating these problems, there are different surface engineering techniques like chemical vapor deposition, physical vapor deposition, sputtering, thermal nitridation, etc. Among all methods, plasma electrolytic processing has advantages like less processing time, use of environmentally friendly electrolytes, economical process, easy scale-up for mass production and etc.The 316L stainless steel was surface-engineered using the cathodic plasma electrolytic process in two different aqueous electrolytes containing urea and acetic acid, which acted as a nitrogen and carbon source, respectively. The processed samples were characterized using a scanning electron microscope to study surface morphology and for qualitative chemical analysis. It revealed the diffusion of nitrogen and carbon into the surface in respective electrolytes. The electrochemical performance of as-received/bare 316L and surface-engineered samples were evaluated in a simulated fuel cell environment (half-cell conditions). The electrolyte comprised 0.5 M H2SO4 with 2 ppm HF at 80 oC, and it was purged with N2 or air to simulate anodic and cathodic conditions, respectively. The potentiodynamic polarization studies revealed similar active-passive behavior for bare 316L and surface-engineered samples. Different electrochemical parameters like corrosion current density (icorr), corrosion potential (Ecorr), and passive current density (ipassive) were deduced. The corrosion potentials for the bare sample were observed to have -0.306 V and -0.316 V in cathodic and anodic conditions, respectively. After surface modification, corrosion potentials shifted to more noble values, i.e., -0.234 V, -0.250 V for samples processed in urea solution and -0.219 V, -0.198 V for samples processed in the acetic acid solution for anodic and cathodic conditions, respectively. But the surface-modified samples showed higher passive current densities for both anodic and cathodic conditions than the bare sample, suggesting inferior passivation ability.Also, long-term potentiostatic studies for 8 hours were conducted to understand the samples' behavior. The current densities at the end of the test were -28.7 µA cm-2 (anodic condition) and 7.5 µA cm-2 (cathodic condition) for bare samples. While the samples processed in urea solution showed 27.4 and 9.0 µA cm-2, and the samples processed in acetic acid solution had -115.5 and 89.8 µA cm-2 of current densities in anodic and cathodic conditions, respectively. At different loads, the interfacial contact resistance measurements between the samples and the gas diffusion layer for all samples were determined. At a load of 140 N cm-2, the bare SS316L and samples processed in urea and acetic acid solution showed values of 118.82, 26.78, and 10.97 mΩ cm2, respectively. These studies suggest plasma electrolytically processed SS316L in acetic acid solution offers the least interfacial contact resistance of 10.97 mΩ cm2 and almost satisfies the Department of Energy target of 10 mΩ cm2 for metallic bipolar plates. A scale-up of coating in a 4×4 cm area and its performance in a single-cell setup will be highlighted.

(Invited) Electron Microscopy Investigation of Electrolyzer Degradation

Low-temperature proton exchange membrane water electrolyzers (PEMWEs) are a key technology for green hydrogen production from renewable energy sources. Developing efficient and durable components for the membrane electrode assembly (MEA) at the heart of the electrolyzer is critical for meeting DOE’s Hydrogen Shot target of $1 per kg of hydrogen by 2031. Of key interest to the efficiency and longevity of the electrolyzer is the anode-side of the MEA, where the costly iridium (Ir) catalyst is prone to dissolution at the high potentials and acidic conditions experienced in the cell. Further, the interfacial contact resistance between the catalyst and porous transport layer (PTL) plays a key role in electrolyzer performance and can degrade over time. Understanding and mitigating these degradation modes is critical for reducing the cost the PEMWEs and enabling commercialization.Here we will present the results of electron microscopy characterization performed on degraded anode catalyst layers and coated PTLs. Cross sections of MEAs submitted to different cycling protocols (square wave, triangle wave, steady-state, etc.) were prepared by diamond-knife ultramicrotomy and studied with in the scanning transmission electron microscope (STEM). Using energy dispersive X-ray spectroscopy (EDS), the dissolution and migration of Ir into the membrane was tracked and correlated with performance losses. The impact of PTL contact area on inhomogeneous degradation in anodes with low catalyst loadings will also be presented. In addition, PTL coating thickness and uniformity will be correlated with interfacial contact resistance measurements using a combination of focused ion beam (FIB), scanning electron microscopy (SEM) and STEM-EDS.Funding for this work was provided by U.S. Department of Energy Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office through the H2NEW Consortium. Electron microscopy research conducted as part of a user project at the Center for Nanophase Materials Sciences (CNMS), which is a US Department of Energy, Office of Science User Facility at Oak Ridge National Laboratory.

Wet powder spraying – A versatile and highly effective technique for the application of spinel-type protective coatings on SOC interconnects

Chromia-forming metallic interconnects used for solid oxide cells require protective coatings to prevent chromium poisoning of other cell components. This study focuses on Mn1.0Co1.9Fe0.1O4 -coated Crofer 22 H interconnects fabricated by wet powder spraying, which is a versatile, cost-effective, and scalable coating technique. The investigation and fine-tuning of relevant parameters along the process chain provide a fundamental understanding of their impact on coating quality and thermomechanical stability. The correlation with cross-sectional analysis and area-specific contact resistance (ASR) measurements supports the parameter evaluation. Mid-term thermal testing demonstrates excellent chromium retention, as well as chemical and mechanical stability of the protective layer on real component interconnect substrates. With an ASR below 10 mΩ cm2 after 1000 h at 800 °C, wet powder spraying represents a viable alternative to established but more expensive processes.

Defining specifications for accurate Metal/TCO specific contact resistivity measurements by TLM in silicon heterojunction devices

Measuring specific contact resistivity (ρc) in test vehicles representative of the final solar cell is critical for interface engineering in high efficiency devices such as silicon heterojunction (SHJ) solar cell. The Transfer Length Method (TLM) is commonly used for layer sheet resistance (Rsheet) and ρc evaluation and is valid for samples with charge transport confined in one conductive layer only. For metal/Transparent Conductive Oxide (TCO) interface ρc evaluation from SHJ cells precursors, there is a need to prevent any contribution from the conductive c-Si. In this work, we investigated by simulation and experimental approach the parameters restricting the current confinement inside the TCO. The first one is the mid-gap trap density (Dit) at the a-Si:H/c-Si interface which has no strong impact on current confinement on simulated TLM test structures. The second one is the variation of the activation energy (Ea=Ec−EF) of the a-Si:H contact layers. Both simulated and experimental results have demonstrated that three current distribution regimes are possible in the TLM test structure depending on the Ea value with only one regime, for Ea between 0.6 and 1.4 eV, enabling to isolate the metal/TCO interface. This condition is mandatory to maintain a sufficiently high potential barrier for electrons at the interfaces a-Si:H(p)/a-Si:H(i)/c-Si(n) and thus lateral current in the TCO layer to apply TLM on SHJ devices.

Effect of Process Pressure on Carbon-Based Thin Films Deposited by Cathodic Arc on Stainless Steel for Bipolar Plates

In this study, three carbon-based coating variants were deposited onto stainless steel substrates, and the process pressure during the carbon layer deposition was varied. We conducted Raman spectroscopy, transmission electron microscopy, interfacial contact resistance measurements, and potentiodynamic polarization tests to examine the effect of the process pressure on the properties of the coatings. The structural characterization revealed that all specimens exhibit a highly sp2-bonded structure. However, some structural differences could also be identified. In the TEM cross-section images of the carbon layer variants, these structural differences could be observed. The carbon layer deposited at 0.98 Pa has some distortions in the mainly perpendicular graphitic structure, which agrees with the Raman results. Almost completely vertically oriented graphitic layers exhibit the 0.1 Pa coating variant with a d-spacing similar to pure graphite. Regarding the contact resistance, the process pressure has only minor influence. All coatings variants have very low resistance values below 3 mΩ cm2, even at a compaction force of 50 N cm−2, which can be attributed to the graphite-like structure. The polarization tests show that the corrosion resistance increases with increasing process pressure. The best coating variant has a corrosion current density of approximately 10−8 A cm−2 and almost 10−6 A cm−2 at room temperature and 80 °C, respectively.

Electrochemical properties and interfacial contact resistance of plasma ion nitrided titanium as PEMFC bipolar plate

Plasma ion nitriding was applied to grade 1 titanium, which was used as a bipolar plate a for proton exchange membrane fuel cell (PEMFC). Electrochemical experiments were performed in a solution of pH3 (Sulfuric acid + 0.1 ppm Hydrofluoric acid, 80 °C) required by the Department of Energy (DoE). Air and hydrogen gas was bubbled to simulate cathode and anode environments, respectively. Several experiments (potentiodynamic polarization and potentiostatic), analyses (XRD, EDS, FE-SEM, and EIS), and interfacial contact resistance measurements were performed to evaluate plasma ion nitrided titanium used as a PEMFC bipolar plate. Plasma ion nitrided titanium showed improved corrosion resistance and interfacial contact resistance compared to the titanium substrate. The nitrided layer was approximately 2.0–2.5 μm, with dense formation of the layer on the titanium substrate. The results of the EDS analysis indicated that a nitrogen diffusion layer of approximately 2.2 μm formed due to interstitial nitrogen atoms.

Comparison of different statistical methods for prediction of lifetime of electrical connectors with short term tests

Lifetime is an important feature defining the reliability of electrical connectors. In general practice, the lifetime tests required for reliability estimation are time and labor intensive. In our previous work, a data driven method using a statistical process, with an application of probability distributions such as standard normal distribution and generalized extreme value (GEV) distribution with negative skewness to predict degradation paths, was introduced for estimation of the lifetime and FIT rate with the help of electrical contact resistance data collected from short term tests. The proposed method proved its significance by showing the possibility of drastic reduction in the lifetime test duration required for reliability determination. In this work, a non-parametric distribution free method using percentiles of actual measured contact resistances is used for determining the lifetime as against the percentiles of probability distribution used in previous work, thereby simplifying the process further and leading to an even more precise estimation. The lifetimes calculated from parametric and non-parametric methods are compared to highlight the significance of distribution free method in reliability estimation.

High-Accuracy Contact Resistance Measurement Method for Liquid Metal by Considering Current-Density Distribution in Transfer Length Method Measurement.

Liquid metals (LMs) are used as stretchable conductors in various stretchable electronic devices. Moreover, such devices using Ga-based LMs have attracted considerable attention. Herein, we propose a method for accurately determining the contact resistance (Rc) between galinstan and Cu electrodes by considering the current-density distribution in transfer length method (TLM) measurement. Conventional TLM measurements assume that the sheet resistance of the metal electrode (Rshe) is negligible compared with that of the object (Rsho), such as Si. However, this assumption may be problematic because the Rsho of Ga-based liquid metals (LMs) is close to the Rshe. Therefore, we developed a method of applying current to each measuring electrode and compared it with the conventional method of applying current to the outer electrodes. Simulation results indicated that Rshe cannot be ignored for galinstan, and the measured resistance in the contact area (RcTotal) included <10% of the Rc component when current was applied to the outer electrodes. In contrast, RcTotal included the entire Rc component when current was applied to each electrode. Furthermore, we found that the volume resistances of the object and electrode included in RcTotal cannot be ignored. Therefore, for accurate measurement, current must be applied to each electrode, and Rc must be determined from the intersections of the measured and simulated RcTotal. The obtained contact resistivity (ρc), i.e., the contact resistance per unit contact area, was 0.115 mΩ·mm2. The maximum error was 0.085 mΩ·mm2, which was lower than the ρc of the solders (≥10-1 mΩ·mm2) with the lowest ρc among the electrical interface materials between the electronic components and wiring. This study provides valuable insight into the Rc measurement of LMs, along with new opportunities for the development of stretchable electronics using LMs.

Validation of methodology to determine the contact resistivity of ECA-based bonds grounded on end–contact resistance measurements using redundant and modified TLM test structures

Accurate determination of the contact resistivity between electrically conductive adhesives (ECAs) and solar metallization paste is a key component of optimizing the electrical performance of bonds based on ECAs, such as shingled joints. This work proposed and validates a methodology that accounts for non–negligible inhomogeneities of test structures based on ECAs and silver screen-printed metallization, such as changes in width of the ECA, to improve the accuracy in the calculation of the contact resistivity. The proposed validation uses statistical theory based on the central limit theorem and the law of large numbers showing that the contact resistivity of bonds based on two different commercially available ECAs can be clearly differentiated with a minimum confidence level of 95% and a maximum error margin of 5%. Moreover, the necessary sample size to achieve such requirements is calculated and shown to be equal to 24 test structures. The validation was done using an acryl-based adhesive loaded with silver flakes (∼10−4 Ω cm), which was compared to an epoxide-based ECA filled with silver–coated copper particles (∼10−3 Ω cm). The validated methodology indicates that the contact resistivity when using the acrylic conductive adhesive is 0.1791 ± 0.0766 mΩ cm2 while when using the epoxide-based adhesive is 0.5025 ± 0.1218 mΩ cm2. Additionally, it is shown that the standard deviation of the contact resistivity is highly dependent on the composition of the conductive adhesive. Hence, the sample size varies depending on the ECA. It is expected that the presented methodology will be a powerful instrument for developers and researchers in the improvement and optimization of ECAs and ECA bonding processes.

Thermal interdiffusion, microstructure and contact resistivity of NiOx/Ni/p+ poly-Si layer systems for perovskite/TOPCon tandem solar cells during annealing processes

In a recently published article (Lange et al., 2023) [1], we envisioned and discussed a tandem solar cell concept based on a perovskite/TOPCon architecture in p-i-n configuration, that utilizes a p+/n+ polycrystalline silicon (poly-Si) tunnel junction and NiOx as hole transport material of the perovskite top cell. A direct contact of NiOx to p+ poly-Si is inevitable in such a device. We investigated that junction and reported how the contact resistivity of the NiOx/p+ poly-Si junction can be improved by orders of magnitudes by intentionally inserting a nm-thin metallic Ni interlayer at that interface through the formation of nickel silicide.In this contribution, we present comprehensive data on layer stack morphology, composition and interdiffusion and the impact on the measured contact resistivity based on (scanning) transmission electron microscopy (STEM) coupled with energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) of model samples as well as the real contact structures. Diffusion and reaction processes in the NiOx/Ni/p+ poly-Si layer stack are investigated during the annealing in the temperature range between 100 °C and 500 °C for varying Ni interlayer thicknesses of 0, 1.0 and 2.0 nm. Furthermore, two NiOx syntheses routes are investigated: sputter deposition (s-NiOx) and a wet-chemical approach (wc-NiOx). We correlate the improvement of contact resistivity for both systems and temperatures <300 °C in regard to contacts without metallic Ni interlayer with the observation of pinhole formation within the SiOz. We have observed that annealing the Ag/s-NiOx junctions above 300 °C under ambient air leads to rectifying contacts and high contact resistivities due to excessive interdiffusion of Ni, O and Ag.

A hybrid coating of organometallic complex with a silane coupling compound to protect galvannealed (GA) steel from white rust without sacrificing weldability

A unique organic-metallic hybrid coating has been formulated to impede white rust formation on galvannealed (GA) steel strips without hindering weldability. With an optimal concentration ratio of methacrylate silane coupling agent to a titanium (IV) lactate metal complex on the surface of zinc were creating of a network-type nanostructure. Controlling the dry film thickness and curing at 120 °C for 60 s with a chemical roll coater produced a thin film coating (<∼2 μm). Spectroscopic instruments like scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), dynamic contact resistance measurement, and electrochemical impedance spectroscopy (EIS) were used to investigate the coating's surface microstructure, interfacial bonding, anticorrosion, and electrical conductivity characteristics for weldability. The welding properties were tested using the AWS D8.9 standard, and the material was subjected to a simulated salt spray test under ASTM B117 to evaluate anti-corrosion (white rust formation). It was observed that ‘Silane’ to ‘Titania complex’ at a ratio of 0.02 in the formulation was providing excellent performance in terms of anti-corrosion and weldability. This coating has the potential to replace the traditionally used harmful chromate passivation coating over zinc and zinc alloy surfaces in the entire steel industries.

Determination of the Corrosion–Oxidation Turning Point at the Field’s Metal/Chromium Interface by Electrical Contact Resistance Measurement

The correlation of the electrical contact resistance measurement and microanalysis of the Field’s metal (FM)/Cr interface was used to determine the temperature-dependent reactions at the interface. Oxidation of Cr by oxygen contained in FM was identified through a sharp increase of the contact resistance around a certain temperature, above which the following resistance decrease was associated to a corrosion process. The corrosion–oxidation turning point was observed around 390 ± 1.7 °C. Cr saturation in FM combined with complete consumption of the oxygen contained in the FM induced a stabilization of the interface giving a specific contact resistance of about 30 µΩ·cm2.

Nanoscale paraffin layer fabricated using spin coating technique for on-demand removable passivation

Passivation is an essential process in the research and application of reactive and air-sensitive materials, and there has been an increasing demand to develop materials for stable but readily removable temporary passivation layers. Paraffin coating has been suggested as a possible candidate for such applications, which, however, further requires the demonstration of thin paraffin coating with complete surface coverage as well as effective depassivation performance. In this study, we demonstrate on-demand removable passivation using nanoscale paraffin layers fabricated using a spin-coating technique. Based on the Emslie Bonner and Peck's and Mark-Houwink-Sakurada (MHS) equations, eicosane and hexane were selected as the solute and solvent, respectively, to ensure low viscosity for the fabrication of nanoscale paraffin layers, facilitating depassivation process under a vacuum. Optimizing the solution concentration and spin speed generates nanoscale paraffin layers with complete surface coverage, which is confirmed through optical microscopic images and subsequent image processing using Python. The simple removal of the nanoscale paraffin layer through vacuum treatment allows us to revisit a passivated surface underneath, and subsequent contact resistance and x-ray photoelectron spectroscopy measurements evince the suppressed surface oxidation of paraffin-coated silicon samples. These results further attest to the applicability of paraffin coating as an on-demand removable passivation technique.