Mechanism research of negative resistance oscillations characteristics of the silicon magnetic sensitive transistor with long base region

2018 ◽  
Vol 32 (24) ◽  
pp. 1850261
Author(s):  
Yunjia Bai ◽  
Xiaofeng Zhao ◽  
Jiandong Hao ◽  
Dianzhong Wen
Keyword(s):  
Printed Circuit Board ◽  
Deep Level ◽  
Negative Resistance ◽  
Circuit Board ◽  
Base Region ◽  
Collector Current ◽  
Oscillation Phenomenon ◽  
Mems Technology ◽  
Emitter Region ◽  
P Type

A silicon magnetic sensitive transistor (SMST) with the negative resistance oscillation phenomenon is presented in this paper. The SMST of cubic structure is composed of three regions and three electrodes (E, C and B). Two of the regions (collector region and base region) are designed on the top surface of the SMST, and the emitter region is designed at the bottom of the SMST. Using microelectromechanical system (MEMS) technology, the chip is fabricated on [Formula: see text] orientation p-type silicon (near intrinsic) wafer and packaged on printed circuit board (PCB). When collector voltage (V[Formula: see text]) and the base injecting current (I[Formula: see text]) are a certain value, the experimental results show that the collector current (I[Formula: see text]) attains negative resistance oscillation phenomenon and it is influenced by the external magnetic field (B) and temperature (T). Based on the effect of deep-level impurities on the carrier net recombination rate, theoretical analysis demonstrates that the deep-level impurities are the main factors of the appearance for oscillations phenomenon.

Frequency Characteristics Research for the Negative Resistance Oscillations Phenomenon of a Silicon Magnetic Sensitivity Transistor

2015 ◽  
Vol 645-646 ◽  
pp. 120-125 ◽  
Author(s):  
Xiao Feng Zhao ◽  
Yi Fan Li ◽  
Mei Wei Lv ◽  
Dian Zhong Wen ◽  
Hong Quan Zhang
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Oscillation Frequency ◽  
Negative Resistance ◽  
Frequency Characteristics ◽  
High Resistivity ◽  
Collector Current ◽  
Oscillation Phenomenon ◽  
Mems Technology ◽  
Magnetic Sensitivity

A silicon magnetic sensitivity transistor (SMST) with negative resistance oscillations phenomenon is presented in this paper, which is constituted by emitter (E), base (B) and collector (C). The SMST chip is fabricated on <100> orientation high resistivity C-type silicon cup by using MEMS technology. Experiment results show, when external magnetic fieldB=0 T, base injection currentIbis the scope of 1.5mA to 1.7mA andVCEis greater than 4.0V, the collector currentIcappears negative resistance oscillation phenomenon, the oscillation frequency will increase with the increase of theVCE.Icchanges with external magnetic fieldB, whereVCEandIbare constant. With the condition of theIb=1.5 mA andVCE=9.0 V, the oscillation frequency ofB=0 mTand B=-150 mT are 5.88 kHz and 7.60 kHz, respectively.

Degradation Analysis of Thick Film Chip Resistors

2009 ◽  
Author(s):  
Bhanu Sood ◽  
Diganta Das ◽  
Michael H. Azarian ◽  
Michael Pecht
Keyword(s):  
Thick Film ◽  
Printed Circuit Board ◽  
Negative Resistance ◽  
Circuit Board ◽  
High Humidity ◽  
Circuit Boards ◽  
Chemical Modifications ◽  
Current Leakage ◽  
Printed Circuit ◽  
Degradation Analysis

Abstract Negative resistance drift in thick film chip resistors in high temperature and high humidity application conditions was investigated. This paper reports on the investigation of possible causes including formation of current leakage paths on the printed circuit board, delamination between the resistor protective coating and laser trim, and the possibility of silver migration or copper dendrite formation. Analysis was performed on a set of circuit boards exhibiting failures due to this phenomenon. Electrical tests after mechanical and chemical modifications showed that the drift was most likely caused by moisture ingress that created a conductive path across the laser trim.

Origami for Tight Spaces - 3D 250C PCB Assemblies for Control Systems

2019 ◽  
Vol 2019 (HiTen) ◽  
pp. 000034-000038 ◽  
Author(s):  
Piers Tremlett ◽  
Phil Elliot ◽  
Pablo Tena
Keyword(s):  
High Temperature ◽  
Printed Circuit Board ◽  
Real Life ◽  
Circuit Board ◽  
Calibration Data ◽  
Engine Fuel ◽  
Sensors And Actuators ◽  
Pcb Assembly ◽  
Operational Life ◽  
Mems Technology

Printed circuit board (PCB) assemblies must fit into unusual spaces for many real-life, high temperature applications such as sensors and actuators. This paper details the design and manufacture of a complex control circuit for a jet engine fuel flow valve. “Origami” was needed to fit this control circuitry into the tight space in the valve, this was achieved using a high temperature flex rigid PCB assembly. The valve was mounted on a hot section of the engine, and the assembly was tested for its capability to operate at 178°C and withstand multiple thermal cycles of −55°C and 175°C during its operational life. Various component joining media were investigated to extend the life of the assembly. The project also developed a one-time programmable (OTP) memory aimed at up to 300°C operation for on board memory to provide calibration data or boot memory for high temperature microcontrollers or processors. The device was based on Micro-Electro-Mechanical Systems (MEMS) technology.

scholarly journals Development of the micro pixel chamber based on MEMS technology

2018 ◽  
Vol 174 ◽  
pp. 02010 ◽  
Author(s):  
T. Takemura ◽  
A. Takada ◽  
T. Kishimoto ◽  
S. Komura ◽  
H. Kubo ◽  
...  
Keyword(s):  
Printed Circuit Board ◽  
Gamma Ray ◽  
Micro Electro Mechanical System ◽  
Neutron Imaging ◽  
Circuit Board ◽  
X Rays ◽  
Position Resolution ◽  
Dose Monitoring ◽  
Mems Technology ◽  
Fine Position

Micro pixel chambers (μ-PIC) are gaseous two-dimensional imaging detectors originally manufactured using printed circuit board (PCB) technology. They are used in MeV gamma-ray astronomy, medicalimaging, neutron imaging, the search for dark matter, and dose monitoring. The position resolution of the present μ-PIC is approximately 120 μm (RMS), however some applications require a fine position resolution of less than 100 μm. To this end, we have started to develop a μ-PIC based on micro electro mechanical system (MEMS) technology, which provides better manufacturing accuracy than PCB technology. Our simulation predicted the gains of MEMS μ-PICs to be twice those of PCB μ-PICs at the same anode voltage. We manufactured two MEMS μ-PICs and tested them to study their behavior. In these experiments, we successfully operated the fabricatedMEMS μ-PICs and we achieved a maximum gain of approximately 7×103 and collected their energy spectra under irradiation of X-rays from 55Fe. However, the measured gains of the MEMS μ-PICs were less than half of the values predicted in the simulations. We postulated that the gains of the MEMS μ-PICs are diminished by the effect of the silicon used as a semiconducting substrate.

Implementing Fringing Field Sensors in PCB Technology

2010 ◽  
Vol 2010 (DPC) ◽  
pp. 000579-000598
Author(s):  
Robert Dean ◽  
Aditi Rane ◽  
Colin Stevens ◽  
Michael Baginski ◽  
Zane Hartzog ◽  
...  
Keyword(s):  
Moisture Content ◽  
Printed Circuit Board ◽  
Circuit Board ◽  
Interdigitated Electrode ◽  
Water Detection ◽  
Out Of Plane ◽  
Fringing Field ◽  
Mems Technology ◽  
Moisture Content Measurement ◽  
Fringing Fields

Interdigitated electrode structures are well suited for realizing capacitors where a significant percentage of the total capacitance in due to the out of plane fringing fields. An object that interferes with the fringing fields will then change the measurable capacitance between the electrodes. Therefore this configuration can be used as a sensor for the object that interferes with the fringing fields and is called a capacitive fringing field sensor. These types of sensors have been used in many applications, such as water detection, moisture content measurement and as proximity switches. Printed circuit board (PCB) technology is particularly useful for realizing this type of sensor architecture. The interdigitated electrode structures can be patterned in the Cu cladding on one or both sides of the substrate. The solder mask coating can then be used to insulate the electrodes to prevent shorting in the presence of water or other conductive substances. The size and spacing of the electrode structures can be optimized to adjust the sensitivity of the sensor to the measurand of interest. The implementation of this type of sensor in PCB technology has several advantages when compared to traditional MEMS technologies. External electronics can readily be attached to the PCB substrate. Very large sensor panels can be manufactured easily and economically. Other types of MEMS sensors have been implemented in PCB technology in recent years. This sensor is compatible with those types of sensors and could be used to augment sensor suites implemented in PCB MEMS technology. Demonstration prototype fringing field sensors were implemented in PCB technology for measuring the mass of small quantities of water, for measuring soil moisture content and for use as capacitive touch switches.

scholarly journals Fabrication and Characteristics of a SOI Three-Axis Acceleration Sensor Based on MEMS Technology

Micromachines ◽  
2019 ◽  
Vol 10 (4) ◽  
pp. 238 ◽  
Author(s):  
Zhao ◽  
Wang ◽  
Wen
Keyword(s):  
Printed Circuit Board ◽  
Simulation Software ◽  
Silicon On Insulator ◽  
Circuit Board ◽  
Acceleration Sensor ◽  
Microelectromechanical System ◽  
Printed Circuit ◽  
Element Simulation ◽  
Acceleration Vector ◽  
Mems Technology

A silicon-on-insulator (SOI) piezoresistive three-axis acceleration sensor, consisting of four L-shaped beams, two intermediate double beams, two masses, and twelve piezoresistors, was presented in this work. To detect the acceleration vector (ax, ay, and az) along three directions, twelve piezoresistors were designed on four L-shaped beams and two intermediate beams to form three detecting Wheatstone bridges. A sensitive element simulation model was built using ANSYS finite element simulation software to investigate the cross-interference of sensitivity for the proposed sensor. Based on that, the sensor chip was fabricated on a SOI wafer by using microelectromechanical system (MEMS) technology and packaged on a printed circuit board (PCB). At room temperature and VDD = 5.0 V, the sensitivities of the sensor along x-axis, y-axis, and z-axis were 0.255 mV/g, 0.131 mV/g, and 0.404 mV/g, respectively. The experimental results show that the proposed sensor can realize the detection of acceleration along three directions.

Laminate MEMS for Heterogeneous Integrated Systems

2012 ◽  
Vol 1427 ◽  
Author(s):  
G. P. Li ◽  
Mark Bachman
Keyword(s):  
Printed Circuit Board ◽  
Low Cost ◽  
Semiconductor Industry ◽  
Three Dimensional ◽  
Circuit Board ◽  
Integrated Systems ◽  
Mems Devices ◽  
Broad Array ◽  
Mems Technology ◽  
Pcb Manufacturing

ABSTRACTPost semiconductor manufacturing processes (PSM), including packaging and printed circuit board (PCB) manufacturing are now capable of producing trace widths of a few micrometers, high aspect ratio vias, three-dimensional constructions, and highly integrated systems in a single small package. Such PSM technology can in principle be used to manufacture micro electromechanical systems (MEMS) for sensing and actuation applications. Although MEMS are traditionally produced using silicon processes, the broad array of manufacturing approaches available in the packaging industry, including lamination, lithography, etching, electroforming, machining, bonding, etc., and the large number of available materials such as polymers, ceramics, metals, etc., provides greater design freedom for producing functional microdevices. The results of such processes applied to fabricating small systems are heterogeneously integrated MEMS devices. Since lamination of stacked layers is a critical component of this process, we refer to these devices as “laminate MEMS.”In many cases laminate MEMS devices are more suited to their applications than their silicon counterparts, especially for applications such as biomedical, optical, and human computer interface. Furthermore, such microdevices can be built with a high degree of integration, pre-packaged, and at low cost. Indeed, the PCB and packaging industries stand to benefit greatly by expanding their offerings beyond serving the semiconductor industry and developing their own devices and products. This paper illustrates that good quality MEMS devices can be manufactured using packaging style fabrication, particularly using stacks of laminates, and discusses some of the unique benefits of such devices. This laminate MEMS technology promises not only improved methods for manufacturing microdevices but also for heterogeneously integrating them with silicon microelectronics and other components into a single package.

scholarly journals Icing Mitigation by MEMS-Fabricated Surface Dielectric Barrier Discharge

2021 ◽  
Vol 11 (23) ◽  
pp. 11106
Author(s):  
Matthias Lindner ◽  
Andrei V. Pipa ◽  
Norbert Karpen ◽  
Rüdiger Hink ◽  
Dominik Berndt ◽  
...  
Keyword(s):  
Printed Circuit Board ◽  
Dielectric Materials ◽  
Circuit Board ◽  
Dielectric Barrier Discharges ◽  
Micro Electro Mechanical Systems ◽  
Dielectric Barrier ◽  
Suitable Material ◽  
Ice Accumulation ◽  
Mems Technology ◽  
Barrier Discharges

Avoiding ice accumulation on aerodynamic components is of enormous importance to flight safety. Novel approaches utilizing surface dielectric barrier discharges (SDBDs) are expected to be more efficient and effective than conventional solutions for preventing ice accretion on aerodynamic components. In this work, the realization of SDBDs based on thin-film substrates by means of micro-electro-mechanical-systems (MEMS) technology is presented. The anti-icing performance of the MEMS SDBDs is presented and compared to SDBDs manufactured by printed circuit board (PCB) technology. It was observed that the 35m thick electrodes of the PCB SDBDs favor surface icing with an initial accumulation of supercooled water droplets at the electrode impact edges. This effect was not observed for 0.3m thick MEMS-fabricated electrodes indicating a clear advantage for MEMS-technology SDBDs for anti-icing applications. Titanium was identified as the most suitable material for MEMS electrodes. In addition, an optimization of the MEMS-SDBDs with respect to the dielectric materials as well as SDBD design is discussed.

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