WIDE-RANGE HIGH-PRECISION DOUBLE-FILM-INTEGRATED CAPACITIVE PRESSURE SENSOR AND PREPARATION METHOD THEREFOR

摘要

Disclosed are a wide-range high-precision double-film-integrated capacitive pressure sensor and a preparation method therefor. The pressure sensor comprises a glass substrate (8), wherein a first shallow groove (80) and a second shallow groove (81) are arranged in the glass substrate (8); the first shallow groove (80) is in communication with the second shallow groove (81) by means of a thin groove (82); a central position of the second shallow groove (81) is provided with a shallow groove through-hole (83); the shallow groove through-hole (83) extends to a bottom face of the glass substrate (8) from a bottom face of the second shallow groove (81); the first shallow groove (80) is provided with a capacitor (C1) capable of measuring a low pressure difference; the second shallow groove (81) is provided with a capacitor (C2) capable of measuring a high pressure difference; the capacitor (C1) capable of measuring the low pressure difference comprises a bottom electrode plate (1) and a thin pressure sensitive film (2); the capacitor (C2) capable of measuring the high pressure difference comprises a thick pressure sensitive film (4) and a top electrode plate (5); the shallow groove through-hole (83) and the capacitor (C1) capable of measuring the low pressure difference are arranged correspondingly by means of the thin groove (82); and the shallow groove through-hole (83) and the capacitor (C2) capable of measuring the high pressure difference are arranged correspondingly by means of the second shallow groove (81). By means of the capacitor (C1) capable of measuring the low pressure difference and the capacitor (C2) capable of measuring the high pressure difference, the pressure sensor realizes high-precision measurement in a low pressure section and a high pressure section respectively.