REPUBLIC OF SERBIA

MINISTRY OF DEFENCE

www.mod.gov.rs

MINISTRY OF DEFENCE

Material Resources Sector

Defensive Technologies Department

Military Technical Institute

www.vti.mod.gov.rs

SOI PIEZORESISTIVE LOW PRESSURE SENSOR FOR HIGH TEMPERATURE ENVIRONMENTS

MILČE M. SMILJANIĆ,
KATARINA RADULOVIĆ,
ŽARKO LAZIĆ,
VESNA JOVIĆ,
BOGDAN POPOVIĆ

Institute of Chemistry, Technology and Metallurgy-Centre of Microelectronic Technology and Single Crystals (IHTM-CMTM), University of Belgrade, Serbia

E-mail: smilce@nanosys.ihtm.bg.ac.rs

Abstract: A prototype of piezoresistive low pressure sensors for high temperature environments has been fabricated on the Silicon-On-Insulator (SOI) wafers utilizing a novel maskless wet etching technique. The prototype has a structured square diaphragm with a concentric boss. The SOI pressure sensors have piezoresistors dielectrically isolated from each other and from the substrate by silicon dioxide. A high temperature transducer prototype has been made utilizing the fabricated sensor. A high temperature method for pressure measurements has been formed. The transducer prototype performance was measured at temperatures up to 300 ⁰С. These SOI pressure sensors are intended for extreme environmental conditions and high operating temperatures that are often needed in military-grade applications and where it is necessary to perform sensitive low pressure measurements. Some examples include aerospace applications like aircraft engines, wind tunnels, various missiles, etc.

Key words: pressure sensor, piezoresistivity, SOI, low pressure, high temperature