scholarly journals Structure Zone Investigation of Multiple Principle Element Alloy Thin Films as Optimization for Nanoindentation Measurements

Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2113
Author(s):  
Alan Savan ◽  
Timo Allermann ◽  
Xiao Wang ◽  
Dario Grochla ◽  
Lars Banko ◽  
...  
Keyword(s):  
Thin Film ◽  
Magnetron Sputtering ◽  
High Speed ◽  
Energy Input ◽  
Cost Effective ◽  
Deposition Process ◽  
Particle Energy ◽  
Film Material ◽  
High Entropy ◽  
Zone Diagram

Multiple principal element alloys, also often referred to as compositionally complex alloys or high entropy alloys, present extreme challenges to characterize. They show a vast, multidimensional composition space that merits detailed investigation and optimization to identify compositions and to map the composition ranges where useful properties are maintained. Combinatorial thin film material libraries are a cost-effective and efficient way to create directly comparable, controlled composition variations. Characterizing them comes with its own challenges, including the need for high-speed, automated measurements of dozens to hundreds or more compositions to be screened. By selecting an appropriate thin film morphology through predictable control of critical deposition parameters, representative measured values can be obtained with less scatter, i.e., requiring fewer measurement repetitions for each particular composition. In the present study, equiatomic CoCrFeNi was grown by magnetron sputtering in different locations in the structure zone diagram applied to multinary element alloys, followed by microstructural and morphological characterizations. Increasing the energy input to the deposition process by increased temperature and adding high-power impulse magnetron sputtering (HiPIMS) plasma generators led to denser, more homogeneous morphologies with smoother surfaces until recrystallization and grain boundary grooving began. Growth at 300 °C, even without the extra particle energy input of HiPIMS generators, led to consistently repeatable nanoindentation load–displacement curves and the resulting hardness and Young’s modulus values.

Thermal Model of a Thin Film Pulsed Pyroelectric Generator

2016 ◽  
Author(s):  
Nicholas R. Jankowski ◽  
Andrew N. Smith ◽  
Brendan M. Hanrahan
Keyword(s):  
Thin Film ◽  
Power Generation ◽  
Energy Conversion ◽  
High Speed ◽  
High Energy ◽  
High Energy Density ◽  
Working Fluid ◽  
Film Material ◽  
Thermodynamic Cycles ◽  
The Impact

Recent high energy density thin film material development has led to an increased interest in pyroelectric energy conversion. Using state-of-the-art lead-zirconate-titanate piezoelectric films capable of withstanding high electric fields we previously demonstrated single cycle energy conversion densities of 4.28 J/cm3. While material improvement is ongoing, an equally challenging task involves developing the thermal and thermodynamic process though which we can harness this thermal-to-electric energy conversion capability. By coupling high speed thermal transients from pulsed heating with rapid charge and discharge cycles, there is potential for achieving high energy conversion efficiency. We briefly present thermodynamic equivalent models for pyroelectric power generation based on the traditional Brayton and Ericsson cycles, where temperature-pressure states in a working fluid are replaced by temperature-field states in a solid pyroelectric material. Net electrical work is then determined by integrating the path taken along the temperature dependent polarization curves for the material. From the thermodynamic cycles we identify the necessary cyclical thermal conditions to realize net power generation, including a figure of merit, rEC, or the electrocaloric ratio, to aid in guiding generator design. Additionally, lumped transient analytical heat transfer models of the pyroelectric system with pulsed thermal input have been developed to evaluate the impact of reservoir temperatures, cycle frequency, and heating power on cycle output. These models are used to compare the two thermodynamic cycles. This comparison shows that as with traditional thermal cycles the Ericsson cycle provides the potential for higher cycle work while the Brayton cycle can produce a higher output power at higher thermal efficiency. Additionally, limitations to implementation of a high-speed Ericsson cycle were identified, primarily tied to conflicts between the available temperature margin and the requirement for isothermal electrical charging and discharging.

scholarly journals High Strength and Deformation Mechanisms of Al0.3CoCrFeNi High-Entropy Alloy Thin Films Fabricated by Magnetron Sputtering

Entropy ◽  
2019 ◽  
Vol 21 (2) ◽  
pp. 146 ◽  
Author(s):  
Wei-Bing Liao ◽  
Hongti Zhang ◽  
Zhi-Yuan Liu ◽  
Pei-Feng Li ◽  
Jian-Jun Huang ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Magnetron Sputtering ◽  
High Hardness ◽  
Deformation Mechanisms ◽  
High Entropy Alloy ◽  
Alloy Thin Film ◽  
Face Centered Cubic ◽  
High Entropy ◽  
Strength And Deformation

Recently, high-entropy alloy thin films (HEATFs) with nanocrystalline structures and high hardness were developed by magnetron sputtering technique and have exciting potential to make small structure devices and precision instruments with sizes ranging from nanometers to micrometers. However, the strength and deformation mechanisms are still unclear. In this work, nanocrystalline Al0.3CoCrFeNi HEATFs with a thickness of ~4 μm were prepared. The microstructures of the thin films were comprehensively characterized, and the mechanical properties were systematically studied. It was found that the thin film was smooth, with a roughness of less than 5 nm. The chemical composition of the high entropy alloy thin film was homogeneous with a main single face-centered cubic (FCC) structure. Furthermore, it was observed that the hardness and the yield strength of the high-entropy alloy thin film was about three times that of the bulk samples, and the plastic deformation was inhomogeneous. Our results could provide an in-depth understanding of the mechanics and deformation mechanism for future design of nanocrystalline HEATFs with desired properties.

Development of Multilayer Composition Thin Film Thermocouple Cutting Temperature Sensor Based on Magnetron Sputtering

2009 ◽  
Vol 69-70 ◽  
pp. 515-519 ◽  
Author(s):  
Yun Xian Cui ◽  
Bao Yuan Sun ◽  
W.Y. Ding ◽  
F.D. Sun
Keyword(s):  
Thin Film ◽  
Magnetron Sputtering ◽  
High Speed ◽  
Cutting Temperature ◽  
High Speed Steel ◽  
Plasma Source ◽  
Cutting Edge ◽  
Static Calibration ◽  
Ecr Plasma ◽  
Thin Film Thermocouple

In the paper, a new multilayer composition thin film thermocouple was developed, which can accurately measure the temperature nearby cutting edge in convenient and fast ways. By means of advanced Twinned microwave ECR plasma source enhanced Radio Frequency (RF) reaction non-balance magnetron sputtering technique, SiO2 insulating film, NiCr/NiSi sensor film and SiO2 protecting film were deposited on the surface HSS substrate. Both static calibration and dynamic calibration were completed. The results showed that the sensor had good performance, good linearity, quick dynamic response, response time constant was 12.7ms. The temperature near the cutting edge in cutting process of aluminum alloy was measured by the developed sensor. The bonding strength between multiple layer film and substrate of high-speed-steel met the presupposed demands.

Principles and Applications of Wafer Curvature Techniques for Stress Measurements in Thin Films

1988 ◽  
Vol 130 ◽  
Author(s):  
Paul A. Flinn
Keyword(s):  
Thin Film ◽  
Thermal Expansion ◽  
Laser Scanning ◽  
Chemical Vapor ◽  
Deposition Process ◽  
Film Material ◽  
Silicon Nitride Films ◽  
Stress Changes ◽  
Computer Controlled

AbstractMeasurement of the curvature induced in a wafer (or other flat plate) by the stress in a thin film has long been used as a convenient and accurate technique for the determination of the stress. Numerous improvements over the years have led to instruments that provide simple and rapid measurements of stress as a function of the time and temperature for any desired thermal history. A computer controlled instrument using laser scanning will be briefly described and its capabilities and limitations discussed.Applications of the technique to a variety of thin film materials will be discussed. In addition to the effects of differences in thermal expansion, stresses associated with various deposition techniques, gain or loss of material, phase transformations and flow will be considered. In aluminum based systems, themal expansion, plastic flow and phase transformation play major roles. Refractory metals show, in addition, large stresses associated with the deposition process. In inorganic dielectric systems thermal expansion effects are usually relatively small; deposition effects and the gain or loss of material are the dominant effects. Silica based glasses formed by chemical vapor deposition, for example, show large stress changes due to gain or loss of water, and plasma deposited silicon nitride films show large effects associated with hydrogen. Overall, determination of the stress as a function of time and temperature is a valuable part of the evaluation of a thin film material for use in a VLSI device.

Film Stress in High Density Thin Film Interconnect

1989 ◽  
Vol 154 ◽  
Author(s):  
J. Tony Pan ◽  
Steve Poon
Keyword(s):  
Thin Film ◽  
Elastic Modulus ◽  
High Speed ◽  
High Density ◽  
Film Stress ◽  
Processing Temperature ◽  
Copper Films ◽  
Film Material ◽  
Repeated Heating ◽  
Heating And Cooling

AbstractHigh density thin film interconnects are expected to be widely used for multi-chip module application to accommodate next generation high I/O and high speed integrated circuits. These interconnects typically use polyimide as the dielectric, and aluminum or copper (with protective overcoat) as the conductor. The interconnects are typically built on silicon or alumina substrates. Large film stress occurs due to the high processing temperature required to cure polyimide and due to the mismatch in thermal coefficients of expansion (TCE) between the film materials and substrate materials. This work studies film stress for these materials.An instrument which measures thin film stress in-situ at temperatures between 25 and 450°C was used to characterize the stress in polyimide, nickel, and copper films. Two substrate materials, silicon and sapphire, were used in order to extract the TCE and elastic modulus for each film material. Three polyimide materials were evaluated. One of the polyimides studied showed complete stress relaxation at temperatures above 300°C and was almost completely elastic upon heating and cooling between 25 and 300°C. The TCE was calculated to be 41×10−6/°C and the biaxial elastic modulus was 4.0×109 Pascal. The nickel had very low stress asplated, however, high tensile stress was observed after 350°C annealing as a result of TCE mismatch. After first annealing, the nickel was almost completely elastic upon cooling and repeated heating and cooling between 25 and 350°C. Copper, on the other hand, was not completely elastic under similar thermal treatments. High thermal stress caused plastic deformation to occur in copper films. The room temperature stress in copper film after 350°C annealing depended on yield strength instead of TCE mismatch. The stress in these materials and its effects on processing and reliability for high density interconnect will be reported.

Incorporation of Ga in CIGS Absorber Layers Formed by RF-Magnetron Sputtering in Se Vapours

2008 ◽  
Vol 587-588 ◽  
pp. 323-327 ◽  
Author(s):  
Pedro M.P. Salomé ◽  
António F. da Cunha
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Solar Cell ◽  
Magnetron Sputtering ◽  
Depth Profiling ◽  
Rf Magnetron Sputtering ◽  
Deposition Process ◽  
Point Of View ◽  
Sputtering Deposition ◽  
Cell Parameters

Cu(In,Ga)Se2 (CIGS) thin film semiconductors are among the most attractive materials for thin film solar cell applications. Conversion efficiency exceeding 19% has been achieved for CIGS absorber layers deposited by three-stage co-evaporation technique. From a technological point of view the sputtering deposition process is more attractive than thermal co-evaporation, however, solar cell parameters obtained so far are worse. The highest efficiency value reported for co-sputtered CIS thin films is less than 8% and there is no data found for CIGS layers produced by a similar technique. We have developed a hybrid RF-magnetron sputtering/evaporation method for the deposition of the CIGS absorber layer. In this method Cu and In are sequentially sputtered from metallic targets in the presence of Se vapour. Ga depth profiling leads to a band gap grading which is known to play an important role in cell performance. Here, we report the results of our work on three different ways of Ga incorporation into the CIGS thin films. They consisted of sputtering from In-GaSe, Cu-GaSe composite targets and Ga evaporation. The Ga content and distribution across the layer thickness was investigated by AES measurements. The CIGS formation kinetics, structural and compositional studies were performed by SEM, XRD and AES measurements.

Preparation of Ge2Sb2Te5 thin film for Phase Change Random Access Memory by RF Magnetron Sputtering and DC Magnetron Sputtering

2006 ◽  
Vol 918 ◽  
Author(s):  
Shin Kikuchi ◽  
Dong Yong Oh ◽  
Isao Kimura ◽  
Yutaka Nishioka ◽  
Koukou Suu
Keyword(s):  
Thin Film ◽  
Magnetron Sputtering ◽  
Phase Change ◽  
High Speed ◽  
Random Access ◽  
Random Access Memory ◽  
Rf Magnetron Sputtering ◽  
Dc Magnetron Sputtering ◽  
Access Memory ◽  
Target Composition

AbstractPhase Change Random Access Memory [PRAM] is one of the candidate for next generation memory due to its non-volitality, high speed, high density and compatibility with Si-based semiconductor process. Ge2Sb2Te5 [GST] thin film , an active layer in this device, is utilized because it has the well-known property of rapid crystallization without phase separation in erasable compact discs industry.We investigated the difference of the character of the GST thin film with various sputtering methods. 100nm thick GST films were prepared with DC magnetron sputtering and RF magnetron sputtering for this experiment. XRF, XRD,SEM and four point probe measurement are used to analyze the electrical properties of these films.As for the composition of the DC sputtered GST films, Te was insufficient from target composition, while the composition of RF sputtered GST films were almost same as target composition. The RF sputtered GST films were composed of hcp by 400°C annealing. On the other hand, the DC sputtered films were mixed-phase of fcc and hcp. The resistivity of DC Sputtered GST films was higher than RF sputtered film cause of poor crystallinity. The uniformity of RF sputtered film was better than DC sputtered film.

Magnetron Sputtering of NiCr/NiSi Thin-Film Thermocouple Sensor for Temperature Measurement when Machining Chemical Explosive Material

2011 ◽  
Vol 467-469 ◽  
pp. 134-139 ◽  
Author(s):  
Qi Yong Zeng ◽  
Tao Hong ◽  
Le Chen ◽  
Yun Xian Cui
Keyword(s):  
Thin Film ◽  
Magnetron Sputtering ◽  
High Speed ◽  
High Speed Steel ◽  
Vital Role ◽  
Explosive Material ◽  
Silicon Thin Film ◽  
Thin Film Thermocouple ◽  
Thin Film Thermocouples ◽  
Nickel Silicon

Temperature plays a vital role in the machining industry today. A Nickel-Chrome versus Nickel-Silicon thin-film thermocouple system has been established for measuring instantaneous workpiece temperature in chemical explosive material machining. The NiCr/NiSi thin-film thermocouples have been deposited inside high speed steel cutters by magnetron sputtering. The typical deposition conditions are summarized. Static and dynamic calibrations of the NiCr/NiSi thin-film thermocouples are presented. The Seebeck coefficient of the TFTC is 40.4 μV/°C which is almost the same as that of NiCr/NiSi wire thermocouple. The response time is about 0.42ms. The testing results indicate that the developed NiCr/NiSi thin-film thermocouple sensors can respond fast enough to catch the very short temperature pulse and perform excellently when machining chemical explosive material in situ.

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