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Polymer-based thermal interface materials (TIMs) are having pump out problem and could be resolved for reliable application. Solid-based interface materials have been suggested and reported. The purpose of this paper is suggesting thin film-based TIM to sustain the light-emiting diode (LED) performance and electronic device miniaturization.

Consequently, ZnO thin film at various thicknesses was prepared by chemical vapour deposition (CVD) method and tested their thermal behaviour using thermal transient analysis as solid TIM for high-power LED.

Low value in total thermal resistance (R_th-tot) was observed for ZnO thin film boundary condition than bare Al boundary condition. The measured interface (ZnO thin film) resistance {(R_th-bhs) thermal resistance of the interface layer (thin film) placed between metal core printed circuit board (MCPCB) board and Al substrates} was nearly equal to Ag paste boundary condition and showed low values for ZnO film prepared at 30 min process time measured at 700 mA. The T_J value of LED mounted on ZnO thin film (prepared at 30 min.) coated Al substrates was measured to be 74.8°C. High value in junction temperature difference (ΔT_J) of about 4.7°C was noticed with 30 min processed ZnO thin film when compared with Al boundary condition. Low correlated colour temperature and high luminous flux values of tested LED were also observed with ZnO thin film boundary condition (processed at 30 min) compared with both Al substrate and Ag paste boundary condition.

Overall, 30 min CVD processed ZnO thin film would be an alternative for commercial TIM to achieve efficient thermal management. This will increase the life span of the LED as the proposed material decreases the T_J values.

This study aims to investigate the effect of temperature applied at the initial deposition of Aluminium Nitride (AlN) thin-film on a silicon substrate by high-power impulse magnetron sputtering (HiPIMS) technique.

HiPIMS system was used to deposit AlN thin film at a low output power of 200 W. The ramping temperature was introduced to substrate from room temperature to maximum 100°Cat the initial deposition of thin-film, and the result was compared to thin-film sputtered with no additional heat. For the heat assistance AlN deposition, the substrate was let to cool down to room temperature for the remaining deposition time. The thin-films were characterized by X-ray diffraction (XRD) and atomic force microscope (AFM) while the MIS Schottky diode characteristic investigated through current-voltage response by a two-point probe method.

The XRD pattern shows significant improvement of the strong peak of the c-axis (002) preferred orientation of the AlN thin-film. The peak was observed narrowed with temperature assisted where FWHM calculated at 0.35° compared to FWHM of AlN thin film deposited at room temperature at around 0.59°. The degree of crystallinity of bulk thin film was improved by 28% with temperature assisted. The AFM images show significant improvement as low surface roughness achieved at around 0.7 nm for temperature assisted sample compares to 3 nm with no heat applied.

The small amount of heat introduced to the substrate has significantly improved the growth of the c-axis AlN thin film, and this method is favorable in the deposition of the high-quality thin film at the low-temperature process.

The measurement of heat flux is of importance to the development of aerospace engine as basic physical quantities in extreme environment. Heat radiation is one of the basic forms of heat transfer phenomenon. The structure optimizing can improve the performance and infrared absorptivity of the thin film sensor.

This paper designed one kind of thin film heat flux sensor (HFS) with antireflective coating based on transparent conductive oxide thermopile. The introduced membrane structure is so thin that it has little impact on sensor performance. Fabrication of thin film sensors were fabricated by physical vapor deposition (PVD) process.

The steady-state and dynamic response characteristics of the HFS were investigated by calibration platform. The experimental results shown that the absorptivity of the membrane structure (for1070nm) improved compared with that before optimization. The sensitivity of heat flux gauge was 48.56 µV/ (kW/m2) and its frequency response was determined to be about 1980 Hz.

The thin film HFS uses thermopile based on Indium Tin Oxid and In2O3. The antireflective coating is introduced to hot endpoint of HFS to improve sensitivity on laser thermal source. The infrared optical properties of membrane layer structure were investigated. The steady-state and the transient response characteristics of the heat flux sensor were also investigated.

The purpose of this paper is to study the friction and wear behavior of germanium (Ge) thin films deposited by low-pressure chemical vapor deposition method on a chromium (Cr)-nickel (Ni) stainless steel substrate after being exposed to relatively mild sliding conditions (low loads and sliding distances).

Wear and friction experiments were conducted with a 100Cr6 steel ball sliding against flat Ge thin-film-coated stainless steel sheets (ball-on-flat microtribometer, no lubricant, normal loads of 50-100 mN, initial Hertzian contact pressures of 385-485 MPa, total sliding distance up to 200 mm and room temperature).

Scanning electron microscopy results revealed that prepared Ge thin films consisted of two different morphologies: curved nanowires and cone-shaped nano-/microdroplets. Regarding friction and wear characteristics of the investigated samples, the substrates coated with Ge thin films did not affect the coefficient of friction significantly by load. The wear of the base material (Cr-Ni stainless steel) was not observed under the mentioned experimental conditions (see the “Design/methodology/approach” section); however, with increased sliding distance and/or applied load, a rupture of the Ge film and an exposure of the stainless steel substrate to the 100Cr6 ball can be expected. Furthermore, the observations suggest that the smearing of Ge nano- and microstructures, plastically deformed during tribotesting, over the surface exposed to the sliding contact is the dominant tribological process.

For the first time, the tribological interaction between Ge thin film and steel surface was investigated under dry sliding conditions using a ball-on-flat microtribometer, and the obtained results provide a useful base for the further research on tribology of Ge-based thin films.

Nickel phosphorus (Ni−P) thin-films have been electrolessly deposited in an acid-plating bath with the addition of manganese sulfate monohydrate (MSM) to achieve higher resistance for the application of embedded resistor with value beyond 10 KΩ. As this material is being used for fabricating embedded resistors under the addition of MSM, its resistance properties including effects of MSM concentration and plating time on resistances, temperature coefficient of resistance (TCR), and resistance tolerance of embedded resistor were investigated. The paper aims to discuss these issues.

The structure of fabricated Ni−P film was detected by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The properties of substrate, including the surface morphologies, glass transition process and boundary of copper pad and substrate surface, were performed by SEM, dynamic mechanical analysis and optical microscope, respectively. The resistance tolerances of embedded resistors were elaborated from the cases of Ni−P thin-film resistance tolerance and the size effects of resistors, respectively.

The fabricated film was found to be constructed with numerous Ni−P amorphous nanoparticles, which was believed to be the reason of increasing thin-film resistance. The Ni−P thin-films presented over one magnitude order of resistance increasing in the case of MSM concentration varied from 0 to 40 g/L. For the case of TCRs, Ni−P thin-films deposited with 20 g/L MSM exhibited low TCRs of within ±100 ppm/°C Before TR at temperature elevating from 40 to 160°C, indicating that this Ni−P thin-film belongs to the constant TCR materials according to the military standard. For the tolerance of embedded resistor, the tolerance contributed by Ni−P thin-film was obtained to be 9.8 percent, whereas the geometry tolerances were in the range of 0-20 percent according to the geometries of embedded resistor.

For Ni−P thin-film without MSM, its low resistance with around 100 ohm/sq. limit the values of resistor few KΩ and restricted its widespread application of embedded resistor with higher resistance beyond 10 KΩ. The authors introduced MnSO₄ in Ni−P electroless plating process to improve the low resistance of Ni−P thin-film. The resistance was increased over one order of magnitude after added with 40 g/L MnSO₄. Due to the specific structure, as this material is being used for fabricating embedded resistors, the electrical properties and its application properties to verify its appliance in embedded resistor were systematically investigated by means of SEM, TEM, XRD characterizations, TCRs, resistance tolerance analysis, respectively.

Indium tin oxide (ITO) is a material belonging to the group of transparent conductive oxides, which are widely used in many fields of technology including optoelectronics and photovoltaics. However, the properties of ITO thin films depend on many factors. Therefore, the aim of the study was thorough investigation of the properties of sputtered ITO thin films of various thicknesses.

ITO coatings were deposited by magnetron sputtering in pure argon atmosphere using ceramic ITO target. Various deposition times resulted in obtaining thin films with different thickness, which had significant influence on the optoelectronic properties of deposited coatings. In this work the results of investigation of structural, surface, optical and electrical properties were presented.

Increase of the coating thickness caused change of the microstructure from amorphous to nanocrystalline and occurrence of grains with a size of 40 to 60 nm on their surface. Moreover, the fundamental absorption edge was red-shifted, whereas the average transmission in the visible wavelength range remained similar. Increase of the thickness caused considerable decrease of the sheet resistance and resistivity. It was found that even thin films with a thickness of 10 nm had antistatic properties.

The novelty and originality of presented work consists in, among other, determination of antistatic properties of ITO thin films with various sheet resistances that are in the range typical for dielectric and semiconducting material. To date, there are no reports on such investigations in the literature. Reported findings might be very helpful in the case of, for example, construction of transparent antireflective and antistatic multilayers.

The purpose of this paper is a new thin-film based sensor proposed for sensitive and selective detection of mercury (Hg²⁺) ions in water. The thin-film platform is easy to use and quick for heavy metal ions (HMIs) detection in the picomolar range. Ion-selective self-assembled monolayer's (SAM) of thiol used for the detection of HMIs above the Au/Ti top surface.

A thin-film based platform is suitable for the on-field experiments and testing of water samples. HMIs (antigen) and thiol-based SAM (antibody) interaction results change in surface morphology and topography. In this study, the authors have used different characterization techniques to check the selectivity of the proposed method. This change in the morphology and topography of thin-film sensor checked with Fourier-transform infrared spectroscopy, surface-enhanced Raman scattering spectroscopy, atomic force microscopy and scanning electron microscopy with energy dispersive x-ray analysis used for high-resolution images.

This thin-film based platform is straightforward to use and suitable for real-time detection of HMIs at the picomolar range. This thin-film based sensor platform capable of achieving a lower limit of detection (LOD) 27.42 ng/mL (136.56 pM) using SAM of Homocysteine-Pyridinedicarboxylic acid to detect Hg²⁺ ions.

A thin-film based technology is perfect for real-time testing and removal of HMIs, but the LOD is higher as compared to microcantilever-based devices.

The excessive use and commercialization of nanoparticle (NPs) are quickly expanding their toxic impact on health and the environment. The proposed method used the combination of thin-film and NPs, to overcome the limitation of NPs-based technique and have picomolar (136.56 pM) range of HMIs detection. The proposed thin-film-based sensor shows excellent repeatability and the method is highly reliable for toxic Hg²⁺ ions detection. The main advantage of the proposed thin-film sensor is its ability to selectively remove the Hg²⁺ ions from water samples just like a filter and a sensor for detection at picomolar range makes this method best among the other current-state of the art techniques.

Development of thin film sensors with pH function for noninvasive real-time monitoring of spoilage of packed seafood such as fish, crab and shrimp are described in this study. It is also the purpose of this study to enhance the leaching resistance of the sensors by using a suitable strategy and to quantitatively correlate the sensor’s halochromism with the total volatile amine.

To prepare halochromic sensors with better leaching resistance, biocompatible materials such as starch, agar, polyvinyl alcohol and cellulose acetate along with a halochromic dye were used to prepare the thin film sensors. These thin films were evaluated for monitoring the spoilage of packed seafood at room temperature, 4°C and −2°C up to 30 days. The halochromic sensors were characterized using UV-visible and FT-IR spectroscopy.

CIELab analyses of the halochromism of the thin film sensors revealed that the color changes exhibited by the sensors in response to the spoilage of seafood are visually distinguishable. Further, the halochromic response of the thin films was directly proportional to the amount of total volatile base nitrogen that evolved from the packed seafood. Excellent leaching resistance was observed for the developed thin film sensors. The halochromic property of the sensors is reversible and thus the sensors are recyclable. Besides, the thin film sensors exhibited significant biodegradability.

This study provides insights for use of different biocompatible polymers for obtaining enhanced leaching resistance in halochromic sensors. Further, the color changes exhibited by the sensors are in line with the total volatile amines evolved from the packed seafood. These results highlight the importance of the developed halochromic thin film sensors for real-time monitoring of the spoilage of packed seafood.

The purpose of this research is to study the effect of thickness and surface properties of ZnO solid thin film for heat dissipation application in LED. Heat dissipation in electronic packaging can be improved by applying a thermally conductive interface material (TIM) and hence the junction temperature will be maintained. ZnO is one of the oxide materials and used as a filler to increase the thermal conductivity of thermal paste. The thickness of these paste-type material cannot be controlled which restricts the heat flow from the LED junction to ambient. The controlled thickness is only possible by using a solid thin-film interface material.

Radio Frequency (RF)-sputtered ZnO thin film on Cu substrates were used as a heat sink for high-power LED and the thermal performance of various ZnO thin film thickness on changing total thermal resistance (R _th-tot) and rise in junction temperature were tested. Thermal transient analysis was used to study the performance of the given LED. The influence of surface roughness profile was also tested on the LED performance.

The junction temperature was high (6.35°C) for 200 nm thickness of ZnO thin film boundary condition when compared with bare Cu substrates. Consecutively, low R _th-tot values were noticed with the same boundary condition. The 600 nm thickness of ZnO thin film exhibited high R _th-tot and interface resistance than the other thicknesses. Bond Line Thickness of the interface material was influenced on the interface thermal resistance which was decreased with increased BLT. Surface roughness parameter showed an immense effect on thermal transport, and hence, low R _th (47.6 K/W) value was noticed with low film roughness (7 nm) as compared with bare Cu substrate (50.8 K/W) where the surface roughness was 20.5 nm.

Instead of using thermal paste, solid thin film ZnO is used as TIM and coated Cu substrates were used as a heat sink. The thickness can be controlled, and it is a new approach for reducing the BLT between the metal core printed circuit board and heat sink.

The purpose of this paper is to compare thick and thin film microstripline response to conducting overlay.

Study changes in transmission and reflection of both thick and thin film microstripline due to overlay of polyaniline (PANI) thin film on stainless steel and silver. PANI was deposited by electropolymerisation method using HCl and H₂SO₄.

Transmittance of both the thick and thin film microstripline decreases due to the PANI overlay and reflectance increases. Thin film microstripline is more sensitive to the type of conducting overlay than thick film microstripline. PANI deposited on silver is more absorbing than PANI deposited on stainless steel using HCl acid. The overlay makes the response of the microstripline more dispersive.

The increase in reflectance and decrease in transmittance can provide information about the type of overlay materials. There is need for newer materials which can replace traditional metals for microstrip components. PANI might serve this purpose.