• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.274-274
• /
• 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.

• Proceedings of the KIEE Conference
• /
• 2003.07c
• /
• pp.1529-1531
• /
• 2003

Thick film mechanical sensors can be categorized into four main areas piezoresistive, piezoelectric, piezocapastive and mechanic tube. In this areas, the thick film strain gage is the earliest example of a primary sensing element based on the substrates. The latest thick film sensor is used various pastes that have been specifically developed for pressure sensor application. The screen printing technique has been used to fabricate the pressure sensors on alumina substrate($Al_2O_3$). Thick film capacitive of strain sensing characteristics are reported and dielectric paste based on (Ti+Ba) materials. The electric property of dielectric paste has been studied and exhibit good properly with good gage factor comparable to piezoresistive strain gage. New piezocapacitive strain sensor was designed and tested. The output of capacitive value was good characteristics.

• Journal of Sensor Science and Technology
• /
• v.32 no.6
• /
• pp.470-474
• /
• 2023

In this study, a diaphragm-type pressure sensor was developed using multi-layer(four-layer) graphene produced at 1 nm thickness by thermally transferring single-layer graphene produced by chemical vapor deposition (CVD) to a 6" silicon wafer. By measuring the gauge factor, we investigated whether it was possible to produce a pressure sensor of consistent quality. As a result of the measurement, the pressure sensor using multilayer graphene showed linearity and had a gauge factor of about 17.5. The gauge factor of the multilayer graphene-based pressure sensor produced through this study is lower than that of doped silicon, but is more sensitive than a general metal sensor, showing that it can be sufficiently used as a commercialized sensor.

• Journal of Sensor Science and Technology
• /
• v.3 no.1
• /
• pp.19-25
• /
• 1994

When etching rectangular convex corners of silicon using anisotropic etchants such as KOH, deformation of the edges always occurs due to undercutting. Therefore, it is necessary to correct the mass pattern for compensation. Experiments for the compensation method to prevent this phenomenon were carried out. In the result, the compensation pattern of a regular square is suitable for acceleration sensors considering space. With this consequence, silicon piezoresistive acceleration sensor with compensated square pillar type of mass has been fabricated using SDB wafer.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2012.10a
• /
• pp.402-403
• /
• 2012

• Journal of Sensor Science and Technology
• /
• v.14 no.1
• /
• pp.56-61
• /
• 2005

This paper present characteristics of chromium oxide thin-film as piezoresistive sensors, which were deposited on Si substrates by DC reactive magnetron sputtering in an argon-Oxide atmosphere for high temperature applications. The chemical composition, physical and electrical properties and thermal stability ranges of the $CrO_{x}$ sensing elements have studied. $CrO_{x}$ thin films with a linear gauge factor(GF${\fallingdotseq}$15), high electrical resistivity (${\rho}$ = $340{\mu}{\Omega}cm$) and TCR<-55 ppm/$^{\circ}C$ have been obtained. These $CrO_{x}$ thin films may allow high temperature pressure sensor miniaturization to be achieved.

• Journal of Sensor Science and Technology
• /
• v.6 no.6
• /
• pp.430-436
• /
• 1997

A piezoresistive acceleration sensor for 30 G has been fabricated by silicon micromachining method using SDB(silicon direct bonding) wafer. The structure of the piezoresistive acceleration sensor consists of a seismic square pillar type mass and four beams. This structure was fabricated by reactive ion etching and chemical etching using KOH-etchant. The rectangular square structure is used in order to compensate the deformation of the edges due to underetching. The fabricated sensor showed a linear output voltage-acceleration characteristics and its sensitivity was about $88{\mu}V/V{\cdot}g$ from 0 to 10 G.

• Journal of Sensor Science and Technology
• /
• v.33 no.3
• /
• pp.173-178
• /
• 2024

Development of pressure sensors for harsh environments with high pressure, humidity, and temperature is essential for many applications in the aerospace, marine, and automobile industries. However, existing materials such as polymers, adhesives, and semiconductors are not suitable for these conditions and require materials that are less sensitive to the external environment. This study proposed a pressure sensor that could withstand harsh environments and had high durability and precision. The sensor comprised a piezoresistor pattern and an insulating film directly formed on a stainless-steel membrane. To achieve the highest sensitivity, a pattern design method was proposed that considered the stress distribution in a circular membrane using finite element analysis. The manufacturing process involved depositing and etching a dielectric insulating film and metal piezoresistive material, resulting in a device with high linearity and slight hysteresis in the range of a maximum of 40 atm. The simplicity and effectiveness of this sensor render it a promising candidate for various applications in extreme environments.

• Korean Journal of Acupuncture
• /
• v.24 no.3
• /
• pp.105-116
• /
• 2007

Objectives : This study was performed to determine whether a pulse analyzer using array piezoresistive sensor was useful to characterize the variables of pulse wave of hypertentive patients (HT) , compared with those of healthy subjects. Methods : One hundred twenty two subjects participated in this study. Sixty nine subjects had hypertension and fifty three subjects had no specific history or disease associated with hypertension. We used automatic pulse analyzer with array piezoreslstive sensor. Results : Calibrated in Chon, no specific differences was between HT group and the healthy group. Calibrated in Gwan. sum of pulse pressure (SPP) of HT group was higher than that of the healthy group. Calibrated in Cheek, mean of height of main peak (Mm) and height of main peak (h1) of HT group were higher than those of the healthy group. Conclusions : Pulse analyzer was useful to determine the risk degree or development possibility of hypertension.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.42 no.1
• /
• pp.19-24
• /
• 2005

In this paper, the fabrication process of Si pressure sensors utilizing piezoresistive effect was optimized. The efficiency(yield) of the fabrication process for Si piezoresistive pressure sensors was improved by conducting Si anisotrophic etching process after processes of piezoresistors and AI circuit patterns. The position and process parameters for piezoresistors were determined by ANSYS and SUPREM simulators, respectively. The measured thickness of p-type Si piezoresistors from the boron depth-profile measurement was in good agreement with the simulated one from SUPREM simulation. The Si anisotrohic etching process for diaphragm was optimized by adding ammonium persulfate(AP) to tetramethyl ammonium hydroxide (TMAH) solution.