• 센서학회지
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• 제21권2호
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• pp.121-126
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• 2012

Piezoresistive type contact force sensor array is fabricated by (111) Silicon bulk micromachining for continuous blood pressure monitoring. Length and width of the unit sensor structure is $200{\mu}m$ and $190{\mu}m$, respectively. The gap between sensing elements is only $10{\mu}m$. To achieve wafer level packaging, the sensor structure is capped by PDMS soft cap using wafer molding and bonding process with $10{\mu}m$ alignment precision. The resistance change over contact force was measured to verify the feasibility of the proposed sensor scheme. The maximum measurement range and resolution is 900 mm Hg and 0.57 mm Hg, respectively.

• 통합자연과학논문집
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• 제3권2호
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• pp.117-121
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• 2010

Silicon quantum dots base on photoluminescent porous silicon were prepared from an electrochemical etching of n-type silicon wafer (boron-dopped<100> orientation, resistivity of 1~10 ${\Omega}-cm$) and used as a alcohol sensor. Silicon quantum dots displayed an emission band at the wavelength of 675 nm with an excitation wavelength of 480 nm. Photoluminescence of silicon quantum dots was quenched in the presence of alcohol vapors such as methanol, ethanol, and isopropanol. Quenching efficiencies of 21.5, 32.5, and 45.8% were obtained for isopropanol, ethanol, and methanol, respectively. A linear relationship was obtained between quenching efficiencies and vapor pressure of analytes used. Quenching photoluminescence was recovered upon introducing of fresh air after the detection of alcohol. This provides easy fabrication of alcohol sensor based on porous silicon.

• The Journal of the Acoustical Society of Korea
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• 제14권2E호
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• pp.12-18
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• 1995

용량형 압력센서의 거동을 유한요소법으로 해석하였다. 센서는 원형박막과 이를 강성지지대에 연결하는 몇 개의 다리들로 구성이 되면, 센서재료는 실리콘 단결정이다. 성능에 영향을 미치는 센서구조의 형상변화를 유한요소 해석법을 이용하여 알아보았는데, 고려한 변수들은 원형박막의 직경 및 두께, 그리고 다리는 개수 등이다. 이들 변수의 변화에 따른 마이크의 정적거동해석, 동적 거동해석, 그리고 감도해석 등의 결과를 분석하여 제작하고자 하는 총 15개의 미소형 압력센서 구조중 최선의 것을 결정하였다.

• 센서학회지
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• 제18권2호
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• pp.147-153
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• 2009

A thermal flow sensor has been fabricated and characterized, consisting of a center resistive heater surrounded by two upstream and one downstream temperature sensing resistors. The heater and temperature sensing resistors are fabricated from nitrogen-doped(n-type) polycrystalline silicon carbide(poly-SiC) deposited by LPCVD(low pressure chemical vapor deposition) on LPCVD silicon nitride films on a Si substrate. Cavities were etched into the Si substrate from the front side to create suspended silicon nitride membranes carrying the poly-SiC elements. One upstream sensor is located $50{\mu}m$ from the heater and has a sensitivity of $0.73{\Omega}$/sccm with ${\sim}15\;ms$ rise time in a dynamic range of 1000 sccm. N-type poly-SiC has a linear negative temperature coefficient and a TCR(temperature coefficient of resistance) of $-1.24{\times}10^{-3}/^{\circ}C$ from room temperature to $100^{\circ}C$.

• 센서학회지
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• 제2권1호
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• pp.19-27
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• 1993

본 논문은 $n^{+}$ 에피택셜층을 이용한 전기화학 에칭스톱과 글라스-실리콘의 양극 접합기술을 이용하여 저 압력측정을 위한 용량형 압력센서를 제작한 것이다. 제작된 센서는 하이브리드형으로 센서 커패시터와 기준 커패시터를 갖는 센서 칩과 두가지 출력검출회로 칩으로 구성되어 있다. 이 제작된 센서는 다이아프램 크기가 $1.0{\times}1.0 mm^{2}$이고, 두께가 $10{\mu}m$로 제작된 센서는 압력이 인가되지 않을 때 용량의 크기가 7.1 pF이고, 10 KPa 압력에서 감도가 5.2 %F.S.이다. 또 용량을 전압으로 검출하는 컨버터회로를 이용할 경우, $5{\sim}45^{\circ}C$ 온도범위에서 영점 온도특성과 감도 온도특성은 각각 0.051 %F.S./$^{\circ}C$와 0.12 %F.S./$^{\circ}C$ 이다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.274-274
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• 2008

This paper describes on the fabrication and characteristics of a 3C-SiC (Silicon Carbide) micro pressure sensor for harsh environment applications. The implemented micro pressure sensor used 3C-SiC thin-films heteroepitaxially grown on SOI (Si-on-insulator) structures. This sensor takes advantages of the good mechanical properties of Si as diaphragms fabricated by D-RIE technology and temperature properties of 3C-SiC piezoresistors. The fabricated pressure sensors were tasted at temperature up to $250^{\circ}C$ and indicated a sensitivity of 0.46 mV/V*bar at room temperature and 0.28 mV/V*bar at $250^{\circ}C$. The fabricated 3C-SiC/SOI pressure sensor presents a high-sensitivity and excellent temperature stability.

• 한국생산제조학회지
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• 제9권5호
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• pp.105-111
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• 2000

Micronization of sensor is a trend of the silicon sensor development with regard to a piezoresistive silicon pressure sensor, the size of the pressure sensor diaphragm have become smaller year by year, and a microaccelerometer with a size less than 200~300${\mu}{\textrm}{m}$ has been realized. Over the past four or five years, numerical modeling of microsensors and microstructures has gradually been developed as a field of microelectromechanical system(MEMS) design process. In this paper, we study some of the micromachining processes of single crystal silicon(SCS) for the microaccelerometer, and their subsequent processes which might affect thermal and mechanical loads. The finite element method(FEM) has been a standard numerical modeling technique extensively utilized in structural engineering discipline for component design of microaccelerometer. Temperature rise sufficiently low at the suspended beams. Instead, larger temperature gradient can be seen at the bottom of paddle part. The center of paddle part becomes about 5~2$0^{\circ}C$ higher than the corner of paddle and suspended beam edges.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.2254-2256
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• 2000

This paper presents an implantable telemetry LC resonance-type pressure sensor for the measurement of the ventricle pressure. This sensor consists of a capacitor and an inductor. This resonant circuit is magnetically coupled with an external antenna coil. The resonance frequency of the circuit decreases as the sensor capacitance is increased by the applied pressure. The inductance and the capacitance are 428nH and 0.98${\mu}F$, respectively. The resonance frequency is 245.7MHz when the differential pressure is zero. The sensitivity of the sensor is 9.477kHz/Pa.

• 센서학회지
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• 제4권1호
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• pp.29-34
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• 1995

SDB웨이퍼를 이용하여 절대압을 감지할 수 있는 압저항형 실리콘 다이아프램 압력센서를 제조하였다. 제조된 센서는 브릿지 형태로 연결된 4개의 압저항과 인가되는 압력에 대한 기계적인 증폭기 역할을 할 수 있는 다이아프램으로 구성되어 있다. 다이아프램 공극(cavity)을 낮은 진공상태로 만들기 위해 실리콘 다이아프램과 Pyrex 7740유리를 0.02mmHg, $400^{\circ}C$에서 정전 접합하였다. 제조된 센서의 감도와 오프셋 전압은 각각 $30.4{\mu}V/VmmHg$, 30.6mV였다.

• 전자공학회논문지A
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• 제30A권7호
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• pp.82-88
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• 1993

This paper describes fabrication of relative type capacitive pressure sensor to be in great demand for many fields. The fabricated sensor consists of two parts` a sensing diaphragm and a pyrox glass cover. The sensor size is 4.5${\times}3.4mm$^{2})$ and 400$\mu$m thick. To improve the nonlinearity, this sensor is designed a rectangular silicon diaphragm with a center boss structure, and in order to improve the temperature characteristics of the sensor in a packaging process, the sensing element is mounted on the pyrex glass support. Some suggestions toward the design and fabrication of improved sensors have been presented. The zero pressure capacitance, Co of sensor is 26.57pF, and the change of capacitance, ${\Delta}$C is 1.55pF from 0Kgf/Cm$^{2}$ to 1Kgf/Cm$^{2}$ at room temperature. The nonlinearity of the sensor output with center boss diaphragm is 1.29%F.S., and thermal zero shift and thermal sensitivity shift is less than 1.43%F.S./$^{\circ}C$and 0.14% F.S./$^{\circ}C$, respectively.