The invention provides a MEMS polysilicon nanofilm
pressure sensor chip and a manufacturing method thereof, and relates to a sensor
chip and a manufacturing method thereof. The sensor includes a
monocrystalline silicon substrate (1), a
pressure sensing film (4) having the section of a flat polysilicon is arranged on the
silicon substrate, an enclosed cavity (2) is formed between the
pressure sensing film and the substrate by taking silica as a sacrificial layer, the upper surface of the
pressure sensing film (4) is provided with four polysilicon nanofilm force sensing resistors (5), the four polysilicon nanofilm force sensing resistors (5), the pressure sensing film (4), and
metal leads are isolated by insulation
layers (7), the
four force sensing resistors (5) are connected to form a
Wheatstone bridge via the
metal leads to convert the pressure to
voltage to output, and sealed
corrosion holes (3) are arranged outside the edge of the pressure sensing film (4). The sensor preparing method is compatible with
integrated circuit technology and is easy to integrate. The sensor has the characteristics of high
linearity sensitivity, wide operational temperature range, high overload capability, easy integration, and low cost.