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1 – 9 of 9Yingping Hong, Ting Liang, Pinggang Jia, Wenyi Liu, Qiulin Tan, Chen Li, Tingli Zheng, Binger Ge and Jijun Xiong
Physical contact and traditional sensitive structure Physical contact and traditional pressure-sensitive structures typically do not operate well in harsh environments. This paper…
Abstract
Purpose
Physical contact and traditional sensitive structure Physical contact and traditional pressure-sensitive structures typically do not operate well in harsh environments. This paper proposes a high-temperature pressure measurement system for wireless passive pressure sensors on the basis of inductively coupled LC resonant circuits.
Design/methodology/approach
This paper begins with a general introduction to the high-temperature pressure measurement system, which consists of a reader antenna inductively coupled to the sensor circuit, a readout unit and a heat insulation unit. The design and fabrication of the proposed measurement system are then described in detail.
Findings
A wireless passive pressure sensor without an air channel is fabricated using high-temperature co-fired ceramics (HTCC) technology and its signal is measured by the designed measurement system. The designed heat insulation unit keeps the reader antenna in a safe environment of 159.5°C when the passive sensor is located in a 900°C high-temperature zone continuously for 0.5 h. The proposed system can effectively detect the sensor’s resonance frequency variation in a high bandwidth from 1 to 100 MHz with a frequency resolution of 0.006 MHz, tested from room temperature to 500°C for 30 min.
Originality/value
Expensive and bulky equipment (impedance analyzers or network analyzers) restrict the use of the readout method outside the laboratory environment. This paper shows that a novel readout circuit can replace the laboratory equipment to demodulate the measured pressure by extracting the various sensors’ resonant frequency. The proposed measurement system realizes automatic and continuous pressure monitoring in a high-temperature environment with a coupled distance of 2.5 cm. The research finding is meaningful for the measurement of passive pressure sensors under a wide temperature range.
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Shijun Zheng, Ting Liang, Yinpin Hong, Ying Li and Jijun Xiong
The paper aims to highlight a wireless pressure-sensitive micro-device with high pressure sensitivity and accuracy. It is based on the partially stabilized Zirconia (PSZ) ceramic…
Abstract
Purpose
The paper aims to highlight a wireless pressure-sensitive micro-device with high pressure sensitivity and accuracy. It is based on the partially stabilized Zirconia (PSZ) ceramic material which is capable of excellent elasticity and robustness.
Design/methodology/approach
The paper begins with a general introduction to the wireless interrogating method and then the fabrication processes of the device using high temperature co-fired ceramic (HTCC) technology are described in detail.
Findings
A passive wireless micro-device made from a novel material-PSZ ceramic on pressure monitoring is fabricated and tested and the authors proved that the device possesses an advantages over some proposed wireless sensors on interrogating distance. The pressure sensitivity of the device is 336 kHz/bar at readout distance 2.5 cm and that is an excellent property.
Originality/value
The paper shows a new design scheme for wireless pressure measurement. The future application of the wireless device indicates the problem on external packaging and wire connection could be avoided. The allowable interrogation distance between the device and readout circuit reaches 2.5 cm which is mentioned for the first time so far. The distance is long enough to insert a thermal insulation material which can protect the vulnerable readout circuit from harsh environment, so the research finding is meaningful for the modern measurement technology.
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Balázs Illés, Agata Skwarek, Attila Géczy, László Jakab, David Bušek and Karel Dušek
The vacuum vapour phase soldering method was investigated by numerical simulations. The purpose of this study was to examine the temperature changes of the solder joints during…
Abstract
Purpose
The vacuum vapour phase soldering method was investigated by numerical simulations. The purpose of this study was to examine the temperature changes of the solder joints during the vapour suctioning process. A low pressure is used to enhance the outgassing of the trapped gas within the solder joints, which otherwise could form voids. However, the system loses heat near the suction pipe during the suctioning process, and it can result in preliminary solidification of the solder joints before the gas could escape.
Design/methodology/approach
A three-dimensional numerical flow model based on the Reynolds averaged Navier–Stokes equations with the standard k-e turbulence method was developed. The effect of the vapour suctioning on the convective heat transfer mechanism was described by the model. Temperature change of the solder joints was studied at the mostly used substrate and component combinations, as well as at different system settings.
Findings
In the function of the substrate thickness and the component size, the solder joints can lose large amount of heat during the void reduction process, which leads to preliminary solidification before the entrapped gas voids could be removed.
Research limitations/implications
The results provide setting information of vacuum vapour phase technology for appropriate and optimal applications.
Originality/value
The relationship between low pressure generation and convective heat transfer mechanism during vacuum vapour phase soldering has not been studied yet. The possible negative effects of the vapour suctioning process on the solder joint temperature are unknown.
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Darko Belavic, Marko Hrovat, Marko Pavlin and Janez Holc
Diffusion patterning is a dielectric patterning technology, which is used in the screen printed thick film technology for higher density multilayer circuits. This technology is…
Abstract
Diffusion patterning is a dielectric patterning technology, which is used in the screen printed thick film technology for higher density multilayer circuits. This technology is suitable for producing lower cost multichip modules and requires a low additional investment in conventional thick film technology production lines. Comparisons of via resolution capability of diffusion patterning versus conventional thick film technology are described and discussed. Preliminary experimental results obtained with a test circuit showed that 200μm lines and 200μm vias could be achieved with acceptable yield and with minimal modification to standard production lines. The electronic circuit for the pressure sensor was designed and realised with the verified technology as a low‐cost ceramic multichip module. A few results of an investigation of some thick film materials, which comprise the “set” of pastes for diffusion patterning technology, are presented.
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The purpose of this paper is to discuss the requirements for long‐term implantation of electronic devices with a focus on packaging and encapsulation.
Abstract
Purpose
The purpose of this paper is to discuss the requirements for long‐term implantation of electronic devices with a focus on packaging and encapsulation.
Design/methodology/approach
Owing to their intended long‐term use in the human body, implants for electrical stimulation present specific challenges to the engineers. The respective roles of packaging and encapsulation must be clearly understood to make the most of new materials and modern machining technologies. This paper offers an introduction to the current situation and highlights challenges for future developments.
Findings
The innovative application of modern technologies may be useful to tackle key issues of encapsulation and sealing of small electrical devices for long‐term implantation.
Originality/value
Two examples of innovative application of alternative package manufacture and sealing method are described.
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Jingxuan Peng, Jingjing Cheng, Lei Wu and Qiong Li
This paper aims to study a high-temperature (up to 200 °C) data acquisition and processing circuit for logging.
Abstract
Purpose
This paper aims to study a high-temperature (up to 200 °C) data acquisition and processing circuit for logging.
Design/methodology/approach
With the decrease in thermal resistance by system-in package technology and exquisite power consumption distribution design, the circuit worked well at high temperatures environment from both theoretical analysis and real experiments evaluation.
Findings
In thermal simulation, considering on board chips’ power consumption as additional heat source, the highest temperature point reached by all the chips in the circuit is only 211 °C at work temperature of 200 °C. In addition, the proposed circuit was validated by long time high-temperature experiments. The circuit showed good dynamic performance during a 4-h test in a 200-°C oven, and maintained a signal-to-noise ratio of 92.54 dB, a signal-to-noise and distortion ratio of 91.81 dB, a total harmonic distortion of −99.89 dB and a spurious free dynamic range of 100.28 dB.
Originality/value
The proposed circuit and methodology showed great potential for application in deep-well logging systems and other high-temperature situations.
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Keywords
Tanyong Wei, Qiulin Tan, Tao Luo, Guozhu Wu, Shun Tang, Dan-Dan Shen, Chen Li and Jijun Xiong
The purpose of this paper is to propose a pressure-, temperature- and acceleration-sensitive structure-integrated inductor-capacitor (LC) resonant ceramic sensor to fulfill the…
Abstract
Purpose
The purpose of this paper is to propose a pressure-, temperature- and acceleration-sensitive structure-integrated inductor-capacitor (LC) resonant ceramic sensor to fulfill the measurement of multi-parameters, such as the measurement of pressure, temperature and acceleration, simultaneously in automotive, aerospace and aeronautics industries.
Design/methodology/approach
The ceramic-based multi-parameter sensor was composed of three LC tanks, which have their resonant frequencies sensitive to pressure, temperature and acceleration separately. Two aspects from the specific sensitive structure design to the multiple signals reading technology are considered in designing the multi-parameter ceramic sensor. Theoretical analysis and ANSYS simulation are used in designing the sensitive structure, and MATLAB simulation and experiment are conducted to verify the feasibility of non-coverage of multi-readout signals.
Findings
It is found that if the parameters of sensitive structure and layout of the LC tanks integrated into the sensor are proper, the implementation of a multi-parameter sensor could be feasible.
Practical implications
The ceramic sensor proposed in the paper can measure pressure, temperature and acceleration simultaneously in harsh environments.
Originality/value
The paper creatively proposes a pressure-, temperature- and acceleration-sensitive structure-integrated LC resonant ceramic sensor for harsh environments and verifies the feasibility of the sensor from sensitive structure design to multiple-signal reading.
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YanJie Guo, QiuLin Tan, Fei Lu, GuoZhu Wu and Lei Zhang
This paper aims to present a novel wireless passive pressure sensor based on an aperture coupled microstrip patch antenna embedded with an air cavity for pressure measurement.
Abstract
Purpose
This paper aims to present a novel wireless passive pressure sensor based on an aperture coupled microstrip patch antenna embedded with an air cavity for pressure measurement.
Design/methodology/approach
In this paper, the sensitive membrane deformed when pressure was applied on the surface of the sensor and the relative permittivity of the mixed substrate changed, resulting in a change in the center frequency of the microstrip antenna. The size of the pressure sensor is determined by theoretical calculation and software simulation. Then, the sensor is fabricated separately as three layers using printed circuit board technology and glued together at last. The pressure test of the sensor is carried out in a sealed metal tank.
Findings
The extracted resonant frequency was found to monotonically shift from 2.219 to 1.974 GHz when the pressure varied from 0 to 300 kPa, leading to an average absolute sensitivity of 0.817 MHz/kPa.
Research limitations/implications
This pressure sensor proposed here is mainly to verify the feasibility of this wireless passive maneuvering structure, and when the base material of this structure is replaced with some high-temperature-resistant material, the sensor can be used to measure the pressure inside the aircraft engine.
Originality/value
The sensor structure proposed here can be used to test the pressure in a high-temperature environment when the base material is replaced with some high-temperature-resistant material.
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Hui Xiao, Xiaotong Guo, Fangzhou Chen, Weiwei Zhang, Hao Liu, Zejian Chen and Jiahao Liu
Traditional nondestructive failure localization techniques are increasingly difficult to meet the requirements of high density and integration of system in package (SIP) devices…
Abstract
Purpose
Traditional nondestructive failure localization techniques are increasingly difficult to meet the requirements of high density and integration of system in package (SIP) devices in terms of resolution and accuracy. Time domain reflection (TDR) is recognized as a novel positioning analysis technology gradually being used in the electronics industry because of the good compatibility, high accuracy and high efficiency. However, there are limited reports focus on the application of TDR technology to SiP devices.
Design/methodology/approach
In this study, the authors used the TDR technique to locate the failure of SiP devices, and the results showed that the TDR technique can accurately locate the cracking of internal solder joints of SiP devices.
Findings
The measured transmission rate of electromagnetic wave signal was 9.56 × 107 m/s in the experimental SiP devices. In addition, the TDR technique successfully located the failure point, which was mainly caused by the cracking of the solder joint at the edge of the SiP device after 1,500 thermal cycles.
Originality/value
TDR technology is creatively applied to SiP device failure location, and quantitative analysis is realized.
Details