• Proceedings of the Korean Society Of Semiconductor Equipment Technology
• /
• 2006.10a
• /
• pp.198-201
• /
• 2006

In this paper, we fabricated drag force type and pressure difference type gas flow sensor with dry etching technology which used Deep RIE(reactive ion etching) and etching stop technology which used SOI(silicon-on-insulator). we fabricated four kinds of sensor, which are cantilever, paddle type, diaphragm, and diaphragm with orifice type. Both cantilever and paddle type flow sensors have similar sensitivity as 0.03mV/V kPa. Sensitivity of the fabricated diaphragm and diaphragm with orifice type sensor were relatively high as about 3.5mV/V kPa, 1.5mV/V kPa respectively.

• Journal of Advanced Navigation Technology
• /
• v.14 no.3
• /
• pp.432-438
• /
• 2010

In this paper, we propose a system which can perceive status of semiconductor equipment and evaluate its performance. The proposed system acquires the information such acceleration, pressure, temperature and gas sensors in the surrounding semiconductor equipment. After acquiring information, it is sent to server through multi hop transmission. The transmitted data generates 3 steps alarm using context-aware algorithm of unit or multiple event. From the experiment's result of the proposed system, we confirm that the reliability and efficiency of information is more improved about 80% than a system that doesn't use context-aware algorithm. Moreover, this system can be effective status monitoring of semiconductor equipment because lots of client nodes acquire surrounding information.

• Journal of Sensor Science and Technology
• /
• v.33 no.1
• /
• pp.24-29
• /
• 2024

Inkjet printing technology is used to mass-produce displays and electrochemical sensors by dropping tens of pico-liters or less of specific-purpose ink through nozzles, just as ink is sprayed and printed on paper. Unlike the deposition method for vaporizing material in a vacuum, inkjet printing technology can be used for processing even under general atmospheric pressure and has a cost advantage because the material is dissolved in a solvent and used in the form of ink. In addition, because it can only be printed on the desired part, masks are not required. However, a technical shortcoming is the difficulty for commercialization, such as uniformity for forming the thickness and coffee ring effect. As sizes of devices decrease, the need to print electrodes with precision, thinness, and uniformity increases. In this study, we improved the printing and processing conditions to form a homogeneous electrode using Ag ink (DGP-45LT-15C) and applied this for patterning to fabricate a heat sensor. Upon the application of voltage to the heat sensor, the model with an extended width exhibited superior heat performance. However, in terms of sheet resistance, the model yielded an equivalent value of 21.6 Ω/□ compared to the ITO.

• Journal of the Semiconductor & Display Technology
• /
• v.2 no.4
• /
• pp.19-22
• /
• 2003

In this paper, Si anisotropic etching characteristics of tetramethylammonium hydroxide (TMAH)/ammonium persulfate (AP) solutions were investigated to realize the optimum structure of a diaphragm for the piezoresistive pressure sensor application. Due to its low toxicity and its high compatibility with the CMOS processing, TMAH was used as Si anisotropic etchants. The variations of Si etch rate on the etching temperature, TMAH concentration, and etching time were obtained. With increasing the etching temperature and decreasing TMAH concentrations, the Si etch rate is increased while a significant non-uniformity exists on the etched surface because of formation of hillocks on the <100> surface. With the addition of AP to TMAH solution, the Si etch rate is increased and an improvement in flatness on the etching front is observed. The Si etch rate is also maximized with increasing the number of addition of AP to TMAH solution per one hour. The Si square diaphragms of 20$\mu\textrm{m}$ thickness and 100-400 $\mu\textrm{m}$ one-side length were fabricated successfully by adding AP of (5/6)g to 800 ml TMAH solution every 10 minutes.

• Journal of Advanced Marine Engineering and Technology
• /
• v.37 no.4
• /
• pp.384-390
• /
• 2013

The sizes of cryogenic vessels and storage tanks are becoming bigger due to strong demands from semiconductor and LCD industry as well as high-tech electronic industry. Conventional level and pressure gauges used for cryogenic vessels were analog types which made exact measurement difficult for the remained quantity at lower levels due to their poor accuracy. In this study, a design for a digital type gas level gauge which can measure the pressure and level inside of the cryogenic liquefied gas storage tanks has been proposed by using a differential pressure sensor, in which the measured data are monitored by a host PC and are transferred to a mobile printer for data confirmation at local station.

• Journal of Sensor Science and Technology
• /
• v.23 no.2
• /
• pp.114-121
• /
• 2014

We report a polysilicon active area membrane field effect transistor (PSAFET) pressure sensor for low stress deflection of membrane. The PSAFET was produced in conventional FET semiconductor fabrication and backside wet etching. The PSAFET located at the front side measured pressure change using 300 nm thin-nitride membrane when a membrane was slightly strained by the small deflection of membrane shape from backside with any physical force. The PSAFET showed high sensitivity around threshold voltage, because threshold voltage variation was composed of fractional function form in sensitivity equation of current variation. When gate voltage was biased close to threshold voltage, a fractional function form had infinite value at $V_{tn}$, which increased the current variation of sensitivity. Threshold voltage effect was dominant right after the PSAFET was turned on. Narrow transistor channel established by small current flow was choked because electron could barely cross drain-source electrodes. When gate voltage was far from threshold voltage, threshold voltage effect converged to zero in fractional form of threshold voltage variations and drain current change was mostly determined by mobility changes. As the PSAFET fabrication was compatible with a polysilicon FET in CMOS fabrication, it could be adapted in low pressure sensor and bio molecular sensor.

• Journal of Navigation and Port Research
• /
• v.29 no.10 s.106
• /
• pp.871-876
• /
• 2005

Application of semiconductor sensors has been widely spreaded into various industries because those have several merits like easy miniaturization and batch production comparison with previous mechanical sensors. But external conditions such as thermal and repetitive load have a bad effect on sensors's lifetime. Especially, this paper was focused on fatigue life of a interconnect made by various materials. Firstly we implemented the stress analysis for interconnect under thermal load and wording pressure. And the fatigue lifetime of each material was induced by Manson & Coffin Equation using the plastic stress-strain curve obtained by the plastic-elastic Finite Element Analysis. The Fatigue lifetime in its bottom is smaller than others and bending load have not an effect on the fatigue lifetime of the interconnect but the stress distribution.

• Journal of Sensor Science and Technology
• /
• v.13 no.6
• /
• pp.462-472
• /
• 2004

In this study, we measured the blood flow on arm by non-invasive method and implemented a system to measure variation of the blood flow by estimating bio-electrical impedance and arterial pressure according to cuff pressure. The implemented system measured impedance variation according to pressure variation applied by artificial cuff pressure on the measuring position. The system consisted of pressure measuring part and impedance measuring part using 4-electrode method. Pressure measuring part was composed of semiconductor pressure sensor and electronic circuit for signal processing of sensor output signal. In addition, impedance measuring part was composed of constant current source circuit and lock-in amplifier for detecting impedance signal. We conducted experiments of impedance measuring part using standard resistance for performance evaluation of the implemented system. In addition we experimented to estimate variation of the blood flow by measuring impedances of the experimental group. We estimated ratio of the blood flow resistance using mean arterial pressure and variation of the blood flow. As a result the ratio of the blood flow resistance and variation of blood flow were in an inverse relationship with each other and the correlation coefficient was -0.96776.

• Journal of the Microelectronics and Packaging Society
• /
• v.14 no.1
• /
• pp.19-26
• /
• 2007

This study was focused on the feasibility of ultrasonic bonding of Au flip chip bumps for a practical complementary metal oxide semiconductor (CMOS) image sensor with electroplated Au substrate. The ultrasonic bonding was carried out with different bonding pressures and times after the atmospheric pressure plasma cleaning, and then the die shear test was performed to optimize the ultrasonic bonding parameters. The bonding pressure and time strongly affected the bonding strength of the bumps. The Au flip chip bumps were successfully bonded with the electroplated Au substrate at room temperature, and the bonding strength reached approximate 73 MPa under the optimum conditions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2005.10a
• /
• pp.283-288
• /
• 2005

Application of semiconductor sensors has widely spreaded into various industries because those have several merits like easy miniaturization and batch production comparison with previous mechanical sensors. But external conditions such as thermal and repetitive load have a bad effect on sensors's lifetime. Especially, this paper was focused on fatigue life of a interconnect made by various materials. Firstly we implemented the stress analysis for interconnect under thermal load and wording pressure. And the fatigue lifetime of each material was induced by Manson & Coffin Equation using the plastic stress-strain curve obtained by the plastic-elastic Finite Element Analysis.