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The purpose of this study was to deposit Bi₄Ti₃O₁₂ films by electron gun evaporation technique starting from Bi_3.25La_0.75Ti₃O₁₂ as a target without annealing. The films have been deposited on Si(100), on thin film buffer layer of Pt and glass substrates. X-ray diffraction (XRD) was used to analyze structure of the films, which possesses a good structure with (0010) preferred orientation. Electronic behavior of the samples has been studied.

The dependence of both the structure and quality of the BLT thin films on different substrates is studied using XRD. The electrical characteristics were determined using capacitance–voltage (C–V) and current–voltage (I–V) measurements at the frequency of 1 MHz. Optical properties of the grown films deposited on glass substrates were characterized by optical transmittance measurements (UV-Vis).

The XRD analysis approved the crystallographer structure of the prepared Bi₄Ti₃O₁₂ films. The optical properties of deposited film (transmittance and the band gap value) are extracted by UV-Vis spectrum.

High crystalline quality Bi₄Ti₃O₁₂ films have been obtained using different substrates at room temperature by means of electron gun deposition. The electrical and ferroelectric properties of thin films were studied using I–V and C–V measurements. The band gap has been found to be about 3.62 eV for the studied film deposited on glass substrate. Electron beam evaporation technique is the most interesting methods, once considering many advantages; such as its stability, reproducibility, high deposition rate and the compositions of the films are controlled.

The purpose of this paper is to describe, review, classify and analyze the current challenges in three-dimensional printing processes for combined electrochemical and microfluidic fabrication areas, which include printing devices and sensors in specified areas.

A systematic review of the literature focusing on existing challenges is carried out. Focused toward sensors and devices in electrochemical and microfluidic areas, the challenges are oriented for a discussion exploring the suitability of printing varied geometries in an accurate manner. Classifications on challenges are based on four key categories such as process, material, size and application as the printer designs are mostly based on these parameters.

A key three-dimensional printing process methodologies have their unique advantages compared to conventional printing methods, still having the challenges to be addressed, in terms of parameters such as cost, performance, speed, quality, accuracy and resolution. Three-dimensional printing is yet to be applied for consumer usable products, which will boost the manufacturing sector. To be specific, the resolution of printing in desktop printers needs improvement. Printing scientific products are halted with prototyping stages. Challenges in three-dimensional printing sensors and devices have to be addressed by forming integrated processes.

The research is underway to define an integrated process-based on three-dimensional Printing. The detailed technical details are not shared for scientific output. The literature is focused to define the challenges.

The research can provide ideas to business on innovative designs. Research studies have scope for improvement ideas.

Review is focused on to have an integrated three-dimensional printer combining processes. This is a cost-oriented approach saving much of space reducing complexity.

To date, no other publication reviews the varied three-dimensional printing challenges by classifying according to process, material, size and application aspects. Study on resolution based data is performed and analyzed for improvements. Addressing the challenges will be the solution to identify an integrated process methodology with a cost-effective approach for printing macro/micro/nano objects and devices.

Detection of low-frequency pressures such as heart rate in the range of 1 Hz is one of the applications of low-frequency resonator. In this paper, the structure of the resonator is in the form of a plate, whose mathematical model has been extracted according to past works and is reported.

This paper presents an electromechanical microresonator that can be used as an ultra-low-frequency pressure sensor. It is very important to choose the right material for the sensors to have the optimal conditions. In this work, by proposing the innovative use of polytetrafluoroethylene material with low stiffness coefficient, the necessary conditions are provided to reduce the vibration frequency of the resonator.

The proposed design is simulated with the help of COMSOL, and its results are compared with the results of the mathematical model, which are very close to each other. Therefore, by inferring the results, the authors can rely on accurate simulations and finalize the similar designs with full confidence before fabrication.

There are important advantages regarding the geometry of the proposed design structure that is the possibility of detecting a pressure of 1 Pa only with voltages less than 2 V. On the other hand, the pull-in effect causes very low frequencies to be achieved in detection with the help of the proposed resonator. Also, the linear and nonlinear behavior of the resonator by applying different pressures has been studied and reported to find the appropriate operating range of the resonator and its limitations.

Describes the key attributes of MEMS technology and existing and future business opportunities. Discusses the various stages in the fabrication of MEMS devices and offers guidance regarding the selection of processing methods for deposition, lithography and etching. Also describes the MEMS‐Exchange program and associated network of fabrication centres.

Reviews some of the more important technologies used for fabricating microcomponents and systems – bulk silicon micromachining, surface micromachining and LIGA, a process for forming deep microstructures by lithography, electroforming and moulding. Discusses the relative merits of using synchroton, electron beam and excimer laser irradiation. Gives a comb actuator and an electrostatic motor as examples of micromachined components.

Al₂O₃ used as gate dielectric enables exploitation of higher electric field capacity of SiC, improving capacitive coupling and memory retention in flash memories. Passivation of traps at interface and in bulk which causes serious threat is necessary for better performance. The purpose of this paper is to investigate the effect of post-deposition rapid thermal annealing (PDA) and post-metallization annealing (PMA) on the structural and electrical characteristics of Pd/Al2O3/6H-SiC capacitors.

Al₂O₃ film is deposited by ALD; PDA is performed by rapid thermal annealing (RTA) in N₂ at 900°C for 1 min and PMA in forming gas for 10 and 40 min. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements data are studied in addition to capacitance-voltage (C-V) and current-voltage (I-V) characteristics for the fabricated Pd/Al₂O₃/SiC capacitors. Conduction mechanism contributing to the gate leakage current is extracted for the entire range of gate electric field.

RTA forms aluminum silicide at the interface causing an increase in the density of the interface states and gate leakage current for devices with an annealed film, when compared with an as-deposited film. One order improvement in leakage current has been observed for the devices with RTA, after subjecting to PMA for 40 min, compared with those devices for which PMA was carried out for 10 min. Whereas, no improvement in leakage current has been observed for the devices on as-deposited film, even after subjecting to PMA for 40 min. Conduction mechanisms contributing to gate leakage current are extracted for the investigated Al₂O₃/SiC capacitors and are found to be trapfilled limit process at low-field regions; trapassisted tunneling in the mid-field regions and Fowler–Nordheim (FN) tunneling are dominating in high-field regions.

The effect of PDA and PMA on the structural and electrical characteristics of Pd/Al₂O₃/SiC capacitors suitable for flash memory applications is investigated in this paper.

Electro‐Science Laboratories have recently introduced two new mixed‐bonded ternary conductors that form excellent cermet resistor terminations. Made of platinum, palladium, and silver (Pt/Pd/Ag), ESL 9565 and 9566 are more oxidation‐resistant during overglaze firing (500–525°C) than more commonly used palladium/silver (Pd/Ag) metallisations. Therefore they solder wet more easily after overglazing than with Pd/Ag.

The processing techniques and materials utilized in the fabrication of a two-terminal electrostatically actuated micro-electro-mechanical cantilever-arrayed device used for radio frequency tuning applications are presented in this work. The paper aims to discuss these issues.

The process, which is based on silicon surface micromachining, uses spin-coated photoresist as the sacrificial layer underneath the electroplated gold structural material and an insulating layer of silicon dioxide, deposited using plasma enhanced chemical vapour deposition (PECVD), to avoid a short circuit between the cantilever and the bottom electrode in a total of six major fabrication steps. These included the PECVD of the silicon dioxide insulating layer, optical lithography to transfer photomask layer patterns, vacuum evaporation to deposit thin films of titanium (Ti) and gold (Au), electroplating of Au, the dry release of the cantilever beam arrays, and finally the wafer dicing to split the different micro devices. These process steps were each sub-detailed to give a total of 14 micro-fabrication processes.

Scanning electron microscope images taken on the final fabricated device that was dry released using oxygen plasma ashing to avoid stiction showed 12 freely suspended micro-cantilevered beams suspended with an average electrostatic gap of 2.29±0.17 μm above a 4,934±3 Å thick silicon dioxide layer. Preliminary dimensional measurements on the fabricated devices revealed that the cantilevers were at least 52.06±1.93 μm wide with lengths varying from 377.97±0.01 to 1,491.89±0.01 μm and were at least 2.21±0.05 μm thick.

The cantilever beams used in this work were manufactured using electroplated gold, and photoresist was used as a sacrificial layer underneath the beams. Plasma ashing was used to release the beams. The beams were anchored to a central electrode and each beam was designed with varying length.

The purpose of this paper is to describe the fabrication of a miniaturized membrane type double cavity vacuum‐sealed micro sensor for absolute pressure using front‐side lateral etching technology.

Potassium hydroxide‐based anisotropic etching of single crystal silicon is used to realize the cavities under the membrane type diaphragms through channels on the sides. The diaphragms consist of composite layers of plasma‐enhanced chemical vapour deposition (PECVD) of silicon nitride and silicon dioxide. PECVD of silicon dioxide is done for sealing the channels and the cavity in vacuum. Boron thermal diffusion in low‐pressure chemical vapour deposition of polysilicon layer over the membrane is done for realizing resistors. The fabricated device uses Wheatstone half bridge circuit to read the variation of resistance with respect to an applied pressure.

A double cavity vacuum‐sealed absolute pressure micro sensor has been fabricated successfully using front‐side lateral etching technology and has been measured for pressure range of 0‐0.45 MPa. The measured pressure sensitivity of two pressure sensors is 9.28 and 10.44 mV/MPa.

The paper shows that front‐side lateral etching technology is feasible in the fabrication of small vacuum‐sealed cavities and absolute pressure sensors.

The purpose of this paper is to electrically examine the quality of thin thermally grown SiO₂ with thickness variation, on Si‐face of 4H‐SiC <0001> (having 50 μm epitaxial layer) by current‐voltage (I‐V) and capacitance‐voltage (C‐V) methods.

Metal‐oxide‐silicon carbide (MOSiC) structures with varying oxide thickness have been fabricated on device grade 4H‐SiC substrate. Ni has been used for gate metal on thermally oxidized Si‐face and a composite layer of Ti‐Au has been used for Ohmic contact on the highly doped C‐face of the substrate. Each structure was diced and bonded on a TO‐8 header with a suitable wire bonding for further testing using in‐house developed LabVIEW‐based computer aided measurement setup.

The leakage current of fabricated structures shows an asymmetric behavior with the polarity of gate bias ( + V or −V at the anode). A strong relation of oxide thickness and temperature on effective barrier height at SiO₂/4H‐SiC interface as well as on oxide charges have been established and reported in this paper.

The paper focuses on the development of 4H‐SiC based device technology in the fabrication of MOSiC‐based integrated structures.