Resistance Uniformity Research Articles

Effects of inclination angle and heat power on heat transfer behavior of flat heat pipe with bionic grading microchannels

Bionic structure has become a popular tool to design heat pipes for its ability of heat transfer enhancement and liquid transport. Inspired by the powerful water collection and transfer capability of pitcher plant surface, this paper presents a new flat heat pipe design with bionic grading microchannels (BGFHP) based on special high-low structured surface. Firstly, the performance advantages of BGFHP are revealed by comparing the heat transfer performance and visible internal flow characteristics of BGFHP and conventional FHP. Secondly, the performance variation and influence trend of BGFHP are investigated experimentally with inclination angle and thermal power as variables. Finally, thermal management effects of natural cooling, FHP and BGFHP in fuel cells are compared to demonstrate the practical application of BGFHP. Results show that the high-low channel structure of BGFHP has the advantages of micro-channel hydraulic transport, and the small channel increases the heat transfer area, circulation efficiency and gas phase flow area, resulting in better start-up time and heat transfer capacity than the traditional FHP. The thermal resistance of BGFHP is reduced by 22%, while the thermal conductivity is increased by more than 40%. In the load range of 10–26 W and inclination angle range of 0–90°, the overall thermal resistance and temperature uniformity of BGFHP decreases and then increases as the inclination angle increases. With the increase of heat power, the thermal resistance of BGFHP gradually decreases, whereas the temperature uniformity first decreases and then increases. The optimal working condition of BGFHP is 45° and 24 W, with a minimum thermal resistance of 0.21 K/W. In the fuel cell temperature control test, the BGFHP was able to maintain the temperature below 52 °C, which is 5 °C lower compared to the FHP. This result shows the advantage of the BGFHP in terms of temperature control.

Mechanistic influence on uniformity of sheet resistance of AlGaN/GaN HEMT grown on Si substrate with the graded AlGaN buffer layers

In this study, the relationship among the wafer bow, dislocations, and transport characteristics of aluminum gallium nitride/gallium nitride (AlGaN/GaN) high electron mobility transistor (HEMT) grown on the silicon substrate using conventional AlGaN buffer layers was comprehensively investigated. It is speculated herein that the mechanism that affects the uniformity of sheet resistance is the uneven distribution of stress in GaN-based HEMT and the wafer bow it generates. The bow can lead to the difference in mobility through affecting the threading dislocations, resulting in poor uniformity of resistance. This conjecture was supported by the results of high-resolution X-ray diffraction, non-contact Hall measurement, Raman spectroscopy, and sheet resistance measurements. To further investigate this problem, a model was proposed to explain it from the perspective of formation mechanism.

Two-phase mixture simulation of the performance of a grooved helical microchannel heat sink filled with biologically prepared water-silver nanofluid: Hydrothermal characteristics and irreversibility behavior

• A novel heatsink with grooved helical microchannels is suggested. • Biologically synthesized water-Ag nanofluid is considered as the working fluid. • First and second law analysis of nanofluid flow inside the heatsink are evaluated. • Heatsink with staggered grooved helical channels has best first-law performance. • Grooving the helical channel entails an increment in the entropy generation. The present paper investigates the influence of using two grooved channel geometries on the hydrothermal performance of a helical microchannel heat sink. The results were compared with those obtained for the plain channel geometry. Based on the results, the highest flow mixing is observed for the staggered grooved configuration. Moreover, the convective heat transfer coefficient enhances by nearly 70% and 17% for the MCHS with the staggered and parallel grooved channels, respectively, as compared to that with the plain channel. The influence of Reynolds number ( Re ) escalation on the convective heat transfer coefficient is insignificant, while a 21% increase is obtained when NF concentration is increased from 0% to 1%. Furthermore, the increase of φ in the grooved configurations is more effective than that in the plain configuration. In addition, the lowest thermal resistance and temperature uniformity factors were obtained for the staggered grooved configuration. Besides, the parallel grooved configuration represents the highest frictional entropy generation rates among the three studied geometries due to the considerable reduction of the fluid flow cross-section area between the groove ribs. The highest heat transfer coefficient and pressure drop are associated with the staggered grooved configuration. For the plain, parallel grooved, and staggered grooved configurations, the increase of Re from 500 to 2000 escalates the NF pressure drop by 2730%, 4420%, and 4460%, respectively. Therefore, the highest performance evaluation criterion of more than unity was obtained for the MCHS with the staggered grooved channels for the studied range of Re (500–2000). The numerical analysis was also performed to evaluate the influence of groove pitch on the hydrothermal performance of the staggered groove channel for the pitch range of 0.15 mm to 0.75 mm. The results demonstrated that the highest PEC is associated with the groove pitch of 0.75 mm.

Preparation of Al<sub>2</sub>O<sub>3</sub> tunnel barrier layer in atome-level controlled Josephson junction

The AlO<sub><i>X</i></sub> tunnel barrier in Josephson junctions prepared by conventional thermal oxidation method is formed by diffusing high-purity oxygen into the surface of Al. But the tunnel barrier fabricated by this method is not completely oxidized, and the thickness of barrier is hard to control accurately. In this work, we use atomic layer deposition to grow Al<sub>2</sub>O<sub>3</sub> tunnel barrier on the surface of Ti. The sandwich structure of Ti/Al<sub>2</sub>O<sub>3</sub>/Ti Josephson junction is grown layer by layer. We investigate the corresponding microstructure and electrical properties by adjusting the thickness of the Al<sub>2</sub>O<sub>3</sub> tunnel barrier and the area of the junction. The experimental results show that the monolayer Al<sub>2</sub>O<sub>3</sub> film is about 1.17 Å (1 Å = 10<sup>–10</sup> m), which is grown by atomic layer deposition, achieves atomic-level controlled thickness. The resistance is controlled by adjusting the barrier thickness at room temperature. And we obtain a Josephson junction with good resistance uniformity at room temperature by optimizing the junction area.

Electronic Structure Reconfiguration of Self-Supported Polyoxometalate-Based Lithium-Ion Battery Anodes for Efficient Lithium Storage.

Polyoxometalate (POM)-based materials are considered as promising candidates for lithium-ion batteries (LIBs) due to their stable and well-defined molecular structure and reversible multielectron redox properties. Currently, POM-based electrode materials suffer from high interfacial resistance and low uniformity. Herein, we reported a self-supported POM-based anode material for LIBs by electrodepositing H3PMo12O40 (PMo12) and aniline on carbon cloth (CC) for the first time. The as-prepared polyaniline (PANi)-PMo12/CC composite exhibited an excellent reversible capacity of 1092 mA h g-1 for 200 cycles at 1 A g-1. Such an outstanding performance was attributed to the rapid electron transfer and Li+ diffusion stemming from the exposure of more active sites by the self-supported structure, the strong electrostatic interaction, and electronic structure reconfiguration between the active PMo12 cluster and conductive PANi polymer. This work provides insight into the electronic structure engineering of highly efficient LIB anode materials.

Optimization and analysis of the acoustic and resistance performance of the plenum chamber via sample entropy and large eddy simulation

The noise of the plenum chamber plays an important role in the acoustic performance evaluation of ventilation and air condition (VAC) systems. The large eddy simulation (LES) model and Ffowcs Williams & Hawkings (FW–H) equation were used to obtain the transient flow and aerodynamic noise, respectively, and a continuous and uniform impedance boundary condition was introduced to calculate the transmission loss (TL) of the perforated board plenum chamber. The aerodynamic noise, TL, resistance and velocity uniformity distribution characteristics of the plenum chamber were predicted by numerical simulation. A full-scale test bed was built to verify the flow field prediction results, and the acoustic prediction results were verified by analog experiments. In addition, based on the sample entropy theory, the pressure fluctuation on the inner surface of the plenum chamber was evaluated. The results show that the perforated board changes the vortex structure in the plenum chamber and reduces the local resistance and the pressure fluctuation on the inner surface wall, and the local resistance coefficient can be reduced by up to 34%. However, the coefficient of velocity uniformity in the plenum chamber decreases by 4%. Furthermore, the perforated board can significantly reduce the TL and peak sound pressure level (SPL) of the plenum chamber. At the receiving point, the overall SPL can be reduced by up to 2.5 dB.

Optimization of learning algorithms in multilayer perceptron (MLP) for sheet resistance of reduced graphene oxide thin-film

<div>Multilayer perceptron (MLP) optimization is carried out to investigate the classifier's performance in discriminating the uniformity of reduced Graphene Oxide(rGO) thin-film sheet resistance. This study used three learning algorithms: resilient back propagation (RP), scaled conjugate gradient (SCG) and levenberg-marquardt (LM). The dataset used in this study is the sheet resistance of rGO thin films obtained from MIMOS Bhd. This work involved samples selection from a uniform and non-uniform rGO thin-film sheet resistance. The input and output data were under going data pre-processing: data normalization, data randomization and data splitting. The data were dividedin to three groups; training, validation and testing with a ratio of 70%: 15%: 15%, respectively. A varying number of hidden neurons optimized the learning algorithms in MLP from 1 to 10. Their behavior helped establish the best learning algorithms in discriminating MLP for rGO sheet resistance uniformity. The performances measured were the accuracy of training, validation and testing dataset, mean squared errors (MSE) andepochs. All the analytical work in this study was achieved automatically via MATLAB software version R2018a. It was found that the LM is dominant inthe optimization of a learning algorithm in MLP forrGO sheet resistance.The MSE for LM is the most reduced amid SCG and RP.</div><div> </div>

Fast Welding of Silver Nanowires for Flexible Transparent Conductive Film by Spatial Light Modulated Femtosecond Laser

Silver nanowires (AgNWs) conductors with fine flexibility and high conductivity have been considered to have a promising perspective in the area of flexible transparent electrode. However, many challenges still exist in improving the conductivity of AgNWs films, such as high temperature and time‐consuming. Herein, an efficient and rapid method to weld AgNWs by spatial light modulated femtosecond (fs) laser is proposed. The Gaussian laser beam is modulated into a line‐shaped laser beam with the length of 773 μm. Compared with traditional spherical lens focus irradiation welding, the welding efficiency can be improved up to tens of times. The mechanism of fs laser welding is mainly to use high‐energy laser beam irradiation to generate local field enhancement which causes local high temperature at the nanowire junction. After laser welding, the sheet resistance of AgNWs films can be reduced to 14.7 Ω sq−1 at the transmittance of 89.5% without substrate damage. The welded AgNWs films exhibit excellent electrical conductivity even after 10 000 bending cycles. Moreover, the welded AgNWs films are used to make a flexible transparent heater, showing superior sheet resistance uniformity.

Thermohydraulic performance of a nanofluid in a microchannel heat sink: Use of different microchannels for change in process intensity

The effects of particle shape on the thermohydraulic performance of a boehmite nanofluid in a microchannel heat sink (MCHS) with different cross-sections are investigated. This investigation is performed for five nanoparticle shapes (platelet, cylinder, blade, brick, and oblate spheroid) at four Reynolds numbers in the MCHS with four cross-sections (i.e., circular, triangular, hexagonal, and elliptical). The MCHS with triangular microchannels demonstrates the greatest heat transfer coefficient, followed by the MCHSs with elliptical, hexagonal, and circular microchannels, respectively. The best temperature distribution and the lowest thermal resistance are realized for the MCHS with triangular microchannels. Moreover, the MCHS with circular microchannels results in the highest Figure of Merit (FoM), while the MCHS with triangular ones demonstrates the lowest FoM. The nanofluid with platelet particles causes the highest pressure loss, whereas the one with the Os-shaped particles has the lowest pressure loss. For all the nanoparticle shapes and cross-sections, uniformity of temperature distribution (θ) and thermal resistance reduce, while the heat transfer coefficient, pressure drop, and pumping power increase by rising the Reynolds number. Additionally, the colloid with the platelet-shaped particles causes the greatest heat transfer coefficient, pursued by the nanofluids with the cylinder-, blade-, brick-, and Os-shaped particles, respectively.

Improvement of Resistive Switching Performance in Sulfur-Doped HfOx-Based RRAM.

In order to improve the electrical performance of resistive random access memory (RRAM), sulfur (S)-doping technology for HfOx-based RRAM is systematically investigated in this paper. HfOx films with different S-doping contents are achieved by atmospheric pressure chemical vapor deposition (APCVD) under a series of preparation temperatures. The effect of S on crystallinity, surface topography, element composition of HfOx thin films and resistive switching (RS) performance of HfOx-based devices are discussed. Compared with an undoped device, the VSET/VRESET of the S-doped device with optimal S content (~1.66 At.%) is reduced, and the compliance current (Icc) is limited from 1 mA to 100 μA. Moreover, it also has high uniformity of resistance and voltage, stable endurance, good retention characteristics, fast response speed (SET 6.25 μs/RESET 7.50 μs) and low energy consumption (SET 9.08 nJ/RESET 6.72 nJ). Based on X-ray photoelectron spectroscopy (XPS) data and fitting of the high/low resistance state (HRS/LRS) conduction behavior, a switching mechanism is considered to explain the formation and rupture of conductive filaments (CFs) composed of oxygen vacancies in undoped and S-doped HfOx-based devices. Doping by sulfur is proposed to introduce the appropriate concentration oxygen vacancies into HfOx film and suppress the random formation of CFs in HfOx-based device, and thus improve the performance of the TiN/HfOx/ITO device.

Designing a new heat sink containing nanofluid flow to cool a photovoltaic solar cell equipped with reflector

BackgroundToday, one of the concerns is to reduce the efficiency of photovoltaic solar cells as their temperature rises. Therefore, cooling photovoltaic is one of the challenges that will be addressed in this article. In this paper, the cooling of a photovoltaic cell by a newly designed heatsink is numerically investigated. MethodTwo nanofluids were used to cool the heatsink. The heatsink consists of an Aluminum cover and two main parts in which there are numerous channels with zigzag walls. Moreover, the two-phase mixture method was employed to simulate the nanofluids flow based on finite volume method. The performance of the heatsink and photovoltaic were studied for concentration of the nanoparticles at different Reynolds numbers. FindingsUsing nanofluids increases the heat transfer coefficient but also increases the required pumping power. By adding 2% alumina at the Reynolds number of 150, the heat transfer coefficient increases by 83%. Furthermore, Al2O3/H2O nanofluids has better thermal resistance and temperature uniformity than CuO/H2O nanofluids for heatsink and photovoltaic. The addition of alumina nanoparticles increases the thermal efficiency of photovoltaic while the addition of copper oxide nanoparticles reduces it. Moreover, by increasing the Reynolds number from 50 to 150, the thermal efficiency increased by 7%.

Modifying and Micro-Alloying Effect on Carbon Steels Microstructure

Small additives of elements exhibiting high chemical activity with respect to iron and impurities, included in its composition, have a complex effect on the structure and properties of steel. Moreover, as a result of the modifying and refining effect of micro-additives, the amount, dispersion and morphology of nonmetallic inclusions change, and when alloying the matrix, hardenability, uniformity of structure and resistance to brittle fracture of steels change, too. The article presents a metallographic analysis of carbon steel deoxidized by a complex Са – Ва alloy. Deoxidation of steel using the complex Са – Ва alloy allows significant reducing the content of nonmetallic inclusions, modifying residual nonmetallic inclusions into favorable complexes with their uniform distribution in the volume of steel, and significant increasing the mechanical properties of steel. The high surface activity of barium makes it possible to consider barium as a rather effective modifier. The use of barium in alloys leads to grinding of non-metallic inclusions, homogenization of liquid metal, lowering the liquidus temperature, grinding of primary grains of cast steel, and increasing technological ductility.

Spatial distribution of plasma parameters by a dual thermal-electrostatic probe in RF and DC magnetron sputtering discharges during deposition of aluminum doped zinc oxide thin films

Aluminum doped zinc oxide thin films deposited by magnetron plasma sputtering are essential for various optoelectronic applications. So far, the oxygen negative ions and the atomic oxygen are regarded as responsible for the poor spatial uniformity of thin film resistivity. While various methods are available for thin film characterization, understanding the growth mechanism requires spatial-resolved measurements of plasma parameters. This work uses a dual thermal-electrostatic probe that is able to reveal the spatial distribution of plasma density, electron temperature and plasma potential. The results exhibit a parabolic profile for plasma density and flat profiles for electron temperature and plasma potential, with no correlation with the strong distribution of thin film resistivity that mirrors the erosion track on the target surface.

Application of orthogonal experiment method in foam flooding system composition and injection parameter optimization

Excellent composition and injection parameters of foam system are essential for foam flooding to exert mobility control. This study aims to optimize foam composition and injection parameters to maximize foam mobility control. The concentrations of foaming agent and stabilizer, oil saturation, foam quality, and flow rate served as influencing factors in the orthogonal experiment method with resistance factor (RF) as the evaluation index. Results showed that cores with different permeability levels corresponded to a set of optimal injection parameters. The optimal combination scheme significantly improved mobility control relative to all test groups in the orthogonal experiment, proving the effectiveness of this method in optimizing foam flooding parameters. During the analysis of orthogonal experimental data, in addition to the method of intuitive analysis was adopted to study the influence of a single factor on the RF, the influence of multiple factors interaction on the RF was also explored. Confirmatory tests were performed on the optimal parameters of foam flooding obtained by orthogonal experiments, and the foam propagation at different positions of the core was determined. The degree of pressure fluctuation during foam flooding was measured with the standard deviation ( SD ), which was used to directly measure the strength of the Jamin effect during foam flooding. The RF distribution factor ( D RF ) was introduced to describe the uniformity of foam seepage resistance along the core axis. D RF was used to study the entrance effect on foam to establish seepage resistance. The propagation performance of foam in porous medium is crucial to maximize its mobility control. Foam injectivity in porous medium should be given attention when optimizing the injection parameters of foam flooding. • Optimal injection parameters of foam are studied by orthogonal experiment method. • Obtained the influence trend of five factors on RF under various permeability levels. • Obtained multi-factors interaction effect on RF under various permeability levels. • Introduce SD and D RF to study the propagation characteristics of foam in cores.

Modeling and experimental analysis of an internally-cooled vapor chamber

In recent years, hotspots have become fatal obstacles that prevent chips from normal operation due to the ever-increasing heat flux of the supercomputers. In order to reduce the probability of hotspots and extend the lifetime of chips, the internally-cooled vapor chamber (ICVC) is designed and fabricated to improve the temperature uniformity. Besides, the mathematical and numerical models of the ICVC are built, respectively. The ICVC is featured with a co-designing of liquid cooling and vapor chamber, which can provide more efficient thermal management under high heat flux. The double-layered liquid cooling pipe is embedded in the vapor chamber, where two heat transfer ways of phase change and single-phase are coordinated. The effects of coolant flow rate and heat flux on various thermal parameters, including temperature uniformity, thermal response, thermal resistance, and pressure drop, are experimentally studied. The experimental and simulation temperature distribution and pressure drop are compared. The results show that the ICVC can yield a superior advantage in terms of temperature uniformity, and the minimum total thermal resistance of ICVC can be decreased to 0.044 K/W. Additionally, compared with other related research, the ICVC is more suitable and promising for the thermal management of devices that require low thermal resistance and good temperature uniformity under high heat flux.

Promotion of boron diffusion and gettering by employing thin Al2O3 layer as a reaction barrier

The formation of a boron-rich layer (BRL) is a common phenomenon during the fabrication of boron (B) emitter due to different solubility of B in the silicon oxide layer and the silicon substrate. In our work, we employ alumina oxide (Al2O3) layers as reaction barriers to avoid the production of the silicon oxide layer and eliminate the BRL. The B diffusion in silicon becomes much more accessible that the diffusion concentration and depth are increased dramatically with the absence of BRL. The Al2O3 layer can also improve the uniformity of surface sheet resistance due to its hydrophilic, bringing superior quality of liquid boron source spin coating. We investigate the influence of Al2O3 with different thicknesses and refractive indexes on the B diffusion. The diffusion profiles of B in the silicon capped with Al2O3 become broader as the thicknesses and refractive indexes of Al2O3 increase. Besides, iron is employed as a model impurity to study the gettering effects during the B diffusion. The increase of the maximum B concentration and the total amount of B doping contribute to a superior gettering effect with the interstitial iron concentration decrease from 3.91e12 cm−3 to a minimal value of 1.65e11 cm−3, and the iron concentration even dropped to 7.24e10 cm−3 after attaching a second deposition. We analyze the mechanisms of gettering systematically during the B diffusion. The present work will help deepen the understanding of B doping and the fabrication of B emitter.

Experimental investigation on the thermal performance of vapor chamber in a compound liquid cooling system

To develop an efficient and practicable liquid cooling system for battery thermal management, a compound liquid cooling system combining a grooved aluminum vapor chamber with a one-through flow cold plate was proposed and its thermal performance experimentally was studied. The heating power, coolant flow rate, filling ratio and tilting angle of the vapor chamber were investigated, which had an impact on the thermal resistance and temperature difference on the heating surface. The results showed that the vapor chamber with a 20%~30% filling ratio had the smallest thermal resistance and preferable temperature uniformity in horizontal configuration. Due to the heat and mass transport of phases along the longitudinal direction inside the vapor chamber, the temperature difference of the heating surface arising from the temperature rise of the coolant could be suppressed effectively. To evaluate the suppressed effect on the temperature difference of the heating surface, the suppression ratio was proposed. The suppression ratio on the heating surface rose with the increase in heating power and the decrease in flowing rate. The thermal resistance and temperature uniformity of the vapor chamber deteriorated in tilting configuration. The vapor chamber at a positive tilting angle configuration performed better compared with that at a negative tilting angle configuration. At 20%~30% filling ratio, the suppression ratio of the temperature difference on the heating surface could be achieved at 0.78 under positive tilting angle configuration.

Electroplating coatings on complex profiled models made of conductive and current-conducting plastic

The possibilities of the conductive and nonconductive composite plastics to be used for the complex profiled models made by the 3D prototyping in galvanoplastics are studied. A dissipating ability of the electrolyte by current and by metal using a Mohler slot cell was studied and applied, a visual study of samples was performed, and the weight and thickness of the metal deposited at different parts of the complex profiled surface of the samples was determined both of conductive and nonconductive plastics. The structure of the conductive plastic must ensure the uniformity of the electrical resistance of the material. The weight and size features of the models made of the conductive plastics for electroplating are determined. The optimal parameters of the process of electrochemical formation of the galvanoplastic copper deposits from copper sulfate electrolyte are defined. The advantages and disadvantages of the use of the conductive and nonconductive models are revealed resulting from a comparative analysis. The features of the process of galvanic coatings’ formation are determined for both cases. It is shown that, in the process of the galvanic manufacturing of the products, it is necessary to take into account a high adhesion of the deposited metal to the surface of the models made of the conductive plastic.

Impact of nanoparticle shape on thermohydraulic performance of a nanofluid in an enhanced microchannel heat sink for utilization in cooling of electronic components

In this article, the thermal–hydraulic efficacy of a boehmite nanofluid with various particle shapes is evaluated inside a microchannel heat sink. The study is done for particle shapes of platelet, cylinder, blade, brick, and oblate spheroid at Reynolds numbers ( Re ) of 300, 800, 1300, and 1800. The particle volume fraction is assumed invariant for all of the nanoparticle shapes. The heat transfer coefficient ( h ), flow irregularities, pressure loss, and pumping power heighten by the elevation of the Re for all of the nanoparticle shapes. Also, the nanofluid having the platelet-shaped nanoparticles leads to the greatest h , and the nanofluid having the oblate spheroid particles has the lowest h and smallest pressure loss. In contrast, the nanofluid having the platelet-shaped nanoparticles leads to the highest pressure loss. The mean temperature of the bottom surface, thermal resistance, and temperature distribution uniformity decrease by the rise in the Reynolds number for all of the particle shapes. Also, the best distribution of the temperature and the lowest thermal resistance are observed for the suspension containing the platelet particles. Thereby, the thermal resistance of the nanofluid with the platelet particles shows a 9.5% decrement compared to that with the oblate spheroid particles at Re = 300. For all the nanoparticle shapes, the figure of merit (FoM) uplifts by elevating the Re , while the nanofluids containing the brick- and oblate spheroid-shaped nanoparticles demonstrate the highest FoM values.

Process Co-Optimization of CVD and CMP for Tungsten Metallization

Chemical vapor deposition (CVD) and chemical-mechanical planarization (CMP) of tungsten have been the enabling process technologies for semiconductor manufacturing. Despite the long history and relative maturity, however, their combined effects on the electrical performance and topographic variation of W metallization are scarcely reported in the open literature. A previous work on Cu plating demonstrates the feasibility of reducing topography and improving electrical resistance uniformity by manipulating Cu plating process for superior incoming filling across different patterns and line widths within the die. Adopting the similar concept, this study utilizes SiH4 and WF6 gas chemistry in a CVD-W process optimized for reduced seam formation. 300 mm wafers with varying W overburden thickness are deposited and polished in order to examine the impacts on resulting resistance uniformity across different line widths, and within-die topography. It will be demonstrated that CVD W overburden thickness alone plays a critical role in the performance of W local interconnects across patterns of varying geometry and feature size. Thicker incoming overburden thickness can improve CMP process window and help mitigate variations in sheet resistance plus local and within-die topography, which can perpetuate during down-stream process and impact device performance adversely. Co-optimization of CVD-W and WCMP processes is pivotal to the performance of W metallization.