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To develop a wireless sensor micro‐systems containing all the components of data acquisition system, such as sensors, signal‐conditioning circuits, analog‐digital converter, embedded microcontroller unit (MCU), and RF communication modules. This has now become the focus of attention in many biomedical applications.

The system prototype consists of miniature FSK transceiver integrated with MCU in one small package, chip antenna, and capacitive interface circuitry based on Delta‐sigma modulator. At the base station side, an FSK receiver/transmitter is connected to another MCU unit, which send the received data or received instructions from a PC through a graphical user interface GUI. Industrial, scientific and medical band RF (433 MHz) was used to achieve half duplex communication between the two sides. A digital filtering has been used in the capacitive interface to reduce noise effects forming capacitance to digital converter. All the modules of the mixed signal system are integrated in a printed circuit board of size 22.46 × 20.168 mm.

An innovation circuits and system techniques for building advanced smart medical devices have been discussed. Low‐power consumption and high reliability are among the main criteria that must be given priority when designing such wirelessly powered microsystems. Switched capacitors readout circuits have been found to be suitable for pressure sensing low‐power applications.

The presented wireless prototype needs a second phase of development that will lead to a further reduction in both size and power consumption. Currently, the main limitation of the RF system is the number of working hours according to the selected battery.

The developed system was found to be useful in terms of measuring pressure and temperature in a system of either slow or fast physical change. It would be a good idea to explore the system performance in human or animal trials.

This paper fulfils useful information for capacitive interface circuitries and presents a new short‐range wireless system that has different design features.

This review aims to give an overview about zinc oxide (ZnO) based gas sensors and the role of doping in enhancing the gas sensing properties. Gas sensors based on ZnO thin film are preferred for sensing applications because of their modifiable surface morphology, very large surface-to-volume ratio and superior stability due to better crystallinity. The gas detection mechanism involves surface reaction, in which the adsorption of gas molecules on the ZnO thin film affects its conductivity and reduces its electrical properties. One way to enhance the gas sensing properties is by doping ZnO with other elements. A few of the common and previously used dopants include tin (Sn), nickel (Ni) and gallium (Ga).

In this brief review, previous works on doped-ZnO formaldehyde sensing devices are presented and discussed.

Most devices provided good sensing performance with low detection limits. The reported operating temperatures were within the range of 200̊C –400̊C. The performance of the gas sensors can be improved by modifying their nanostructures and/or adding dopants.

As of yet, a specific review on formaldehyde gas sensors based on ZnO metal semiconductors has not been done.

The dry development of a photoresist is modelled using the analytical solution of the Boltzmann equation. It is proposed that at very low pressure and in the presence of a magnetic field, the etch rate of the resist can be calculated by integrating the ion flux. The simulation results illustrates improvement in both microuniformity and macrouniformity when the resist is etched under these process conditions.

Combination of a number of sensors with different response parameters into sensor arrays would enhance the overall performance of the radiation detection system. This paper presents a conceptual approach to the development of sensor arrays system with instantaneous dose and dose rate readout. A dynamic selection of multiple sensors with various sensitivity and accuracy range is implemented by applying pattern recognition (PR) analysis, which maximizes measurement accuracy. A number of relevant PR methods are discussed.

Thick films based on NiO, ZnO, In₂O₃, CeO₂, TiO₂, CuO and CdO are the key sensing elements in the proposed approach. Pure and carbon‐doped metal oxides were screen‐printed on Si wafers to form pn‐heterojunctions. All devices were exposed to a disc‐type 137 Cs source with an activity of 370 kBq. The values of radiation damage of pn‐junctions were estimated from changes in their current‐voltage characteristics.

Sensors showed an increase in the values of current with the increase in radiation dose up to certain levels, exceeding these levels results in unstable dosimetric characteristics.

The sensitivity of metal oxide films to γ‐radiation exposure depends on their composition and thickness. Mixing the oxides in different proportions and the addition of conducting particles, such as carbon, alters films susceptibility to radiation. In particular, sensors based on such films have dose response characteristics with certain level of sensitivity and working dose range, conditioned by particular sensing material properties and the device structure.

In this paper, simulation of topography effects in photolithography is examined using the two‐dimensional PC based simulator called SLITS (Simulation of Lithography on Topographic Substrates). This program uses FEA software (in‐house written) to solve wave propagation in a photoresist layer and a modified String Algorithm for photoresist development. The simulated results illustrates the effect of topography on the latent and relief images.

Thin films of tellurium dioxide (TeO₂) and indium oxide (In₂O₃) mixtures were investigated for γ‐radiation dosimetry purpose. Samples were fabricated using thermal vacuum evaporation technique. The electrical properties of mixed oxides thin films [(TeO₂)_1−x(In₂O₃)_x, where x=0 and 10 per cent by weight] and their changes under the influence of γ‐radiation were investigated. Samples with contacts having a planar structure showed increase in the values of current with the increase in radiation dose up to a certain dose level. Thin films in the form of pn‐junctions were fabricated with (TeO₂)_1−x(In₂O₃)_x as p‐type material and sulphur as n‐type material. These pn‐junctions exhibited Zener diode behaviour. The current‐voltage characteristics for as‐deposited and γ‐irradiated samples were recorded. The level of response for all the fabricated devices was found to be highly dependent on the composition of the exposed material.

Indium oxide (In₂O₃) and silicon oxide (SiO) mixtures in the form of thick films pn‐junctions were investigated for gamma radiation dosimetry purposes. Polymer pastes of In₂O₃ and SiO mixtures in various proportions were made of 92 wt per cent of functional material and 8 wt per cent of PVB, while ethyleneglycolmonobutylether was used as a solvent. Raman spectroscopy and X‐ray diffraction (XRD) of the films readily endorse the formation of a mixed silicon oxide and indium oxide coating. All devices were exposed to a disc‐type ¹³⁷Cs source with an activity of 370 kBq. The I‐V characteristics for the samples were measured after each exposure dose. Results show that the current is increased with the increase in radiation dose to a certain level, exceeding this level resulted in unstable dosimetric characteristics and device damage. The performance parameters of the devices, such as sensitivity to γ‐radiation exposure and working dose region, were found to be highly dependant on the composition of the materials used.

Telemetry capsules have existed since the 1950s and were used to measure temperature, pH or pressure inside the gastrointestinal (GI) tract. It was hoped that these capsules would replace invasive techniques in the diagnosis of function disorders in the GI tract. However, problems such as signal loss and uncertainty of the pills position limited their use in a clinical setting. In this paper, a review of the capabilities of microelectromechanical systems (MEMS) for the fabrication of a wireless pressure sensor microsystem is presented.

The circuit requirements and methods of data transfer are examined. The available fabrication methods for MEMS sensors are also discussed and examples of wireless sensors are given. Finally, the drawbacks of using this technology are examined.

MEMS for use in wireless monitoring of pressure in the GI tract have been investigated. It has been shown that capacitive pressure sensors are particularly suitable for this purpose. Sensors fabricated for wireless continuous monitoring of pressure have been reviewed. Great progress, especially using surface micromachining, has been made in recent years. However, despite these advances, some challenges remain.

Provides a review of the capabilities of MEMS.

Considering its vast utility in industries, this paper aims to present a detailed review on fundamentals, classification and progresses in pressure sensors, along with its wide area of applications, its design aspects and challenges, to provide state-of-the-art gist to the researchers of the similar domain at one place.

Swiftly emerging research prospects in the micro-electro-mechanical system (MEMS) enable to build complex and sophisticated micro-structures on a substrate containing moving masses, cantilevers, flexures, levers, linkages, dampers, gears, detectors, actuators and many more on a single chip. One of the MEMS initial products that emerged into the micro-system technology is MEMS pressure sensor. Because of their high performance, low cost and compact in size, these sensors are extensively being adopted in numerous applications, namely, aerospace, automobile and bio-medical domain, etc. These application requirements drive and impose tremendous conditions on sensor design to overcome the tedious design and fabrication procedure before its reality. MEMS-based pressure sensors enable a wide range of pressure measurement as per the application requirements.

The paper provides a detailed review on fundamentals, classification and progresses in pressure sensors, along with its wide area of applications, its design aspects and challenges, to provide state of the art gist to the researchers of the similar domain at one place.

The present paper discusses the basics of MEMS pressure sensors, their working principles, different design aspects, classification, type of sensing diaphragm used and illustration of various transduction mechanisms. Moreover, this paper presents a comprehensive review on present trend of research on MEMS-based pressure sensors, its applications and the research gap observed till date along with the scope for future work, which has not been discussed in earlier reviews.

This paper aims to discuss the general principles behind the microwave sensing and demonstrates the potential of cavity microwave resonator device in real-time monitoring for: environmental monitoring with the focus on wastewater pollution, a system for oil/gas/water content evaluation in a dynamic pipeline, a system for real-time determination of bacteria concentration and a method for non-invasive glucose determination.

Microwave sensing is a rapidly developing technology which has been successfully used for various industrial applications including water level measurements, material moisture content, in construction industry for non-invasive evaluation of structures and even in the healthcare industry for non-invasive real-time monitoring of glucose in diabetic patients. Novel microwave cavities designed and tested for specific applications are presented.

The paper provides experimental results of testing the novel microwave sensing systems in a range of industrial and healthcare applications and discusses the potential of these systems for real-time monitoring of processes and parameters.

The concept of real-time microwave sensing was successfully tested, but further experiments are required to account for possible interference mechanisms before it can be used commercially on a large-scale.

It is suggested that a novel approach to wastewater monitoring, namely using specially designed microwave cavity sensors, could lead to a successful development of an advanced platform capable of providing for a real-time detection of water content with superior sensitivity. Also, a system for real-time multiphase fluid composition monitoring is reported, which is essential for sustainable oil industry operation.

The paper illustrated the potential of microwave sensing as a real-time monitoring platform for a broad spectrum of commercial applications, with a focus on system developed by the authors, namely, for the monitoring of a multiphase fluid flow in a dynamic oil pipeline, for real-time monitoring of nutrients concentration in wastewater and for healthcare industry, in particular for real-time non-invasive determination of the glucose levels and bacteria concentration.