High-temperature-resistant silicon-based high-sensitivity strain sensor and preparation method thereof

• Main Authors: CUI CHENKAI, XIE JIEGAO, QIN YAFEI, WEI ERJIONG
• Format: Patent
• Language: Chinese; English
• Published: 19.09.2023
• Subjects: MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; PHYSICS; TESTING

The invention discloses a high-temperature-resistant silicon-based high-sensitivity strain sensor. The high-temperature-resistant silicon-based high-sensitivity strain sensor comprises a monocrystalline silicon layer based on an SOI (Silicon On Insulator) silicon wafer, a thermally oxidized silicon dioxide layer and a thinned monocrystalline silicon layer for improving the strain sensitivity, the four piezoresistors are formed on the monocrystalline silicon layer through magnetron sputtering of metal ions and are perpendicular to one another; the piezoresistor forms an electrically connected heavy ion doped transition region, and the top of the piezoresistor is provided with an insulating layer silicon nitride film covering the whole device; the thickness of the monocrystalline silicon layer 13 is reduced by 50%-70% on the basis of the original thickness. The piezoresistor is of a U-shaped structure, the width of the piezoresistor is 5%-10% of the length of the piezoresistor, the piezoresistor is electrically