Manufacturing method of flexible heat-sensitive thin film resistor array

Abstract

The invention discloses a manufacturing method of a flexible heat-sensitive thin film resistor array, which belongs to the field of micro-electromechanical systems (MEMS). The method comprises the following steps: firstly depositing a sacrificial layer on a silicon chip; spin-coating a PI prepolymer on the sacrificial layer, and forming a PI thin film by thermocuring; then spin-coating photoresist, carrying out lithographic patterning, and sputtering a required metal heat-sensitive thin film layer; adopting the stripping method to obtain a pattern of the heat-sensitive thin film layer; then spin-coating the photoresist, carrying out the lithographic patterning, and then electroplating for forming an electrical connection metal layer; removing the photoresist, and then carrying out heat treatment on heat-sensitive resistors; and finally depositing a parylene protective layer, removing the sacrificial layer and then obtaining the flexible thin film resistor array. The flexible heat-sensitive thin film resistor array has simple process, more reliable connectivity of the heat-sensitive resistors, and small interference of conductor resistance, and can greatly improve the measurement precision when being used as a sensing element of a sensor, and be applied in moist, underwater and other environments under the condition of ensuring the sensitivity of the sensor.

Description

Technical field: [0001] The invention relates to a manufacturing method of a flexible thermosensitive thin film resistance array, which belongs to the field of micro-electromechanical systems (MEMS). Background technique: [0002] Thermistor thin film resistor arrays can be widely used to make sensitive probes for temperature sensors, flow rate sensors, and shear stress sensors. Thermistor thin film resistor arrays are fabricated on polymer flexible film substrates, which are bendable and twistable compared to hard substrates, and can adapt to the distribution of flow field temperature, flow velocity, and shear stress on high-curvature non-flat surfaces. type measurement tasks; especially when used for dynamic measurement of the external flow field, the hard substrate must consider the heat insulation structure between the heat-sensitive element and the substrate, and most polymer materials have good heat insulation, and the polymer flexible There is no need to consider the...

AI Technical Summary

Problems solved by technology

[0005] 1) Although the PDMS interlayer can be separated from the PI film under thermal stress conditions, manual peeling is easy to cause damage to flexible devices, and PDMS is not resistant to high temperatures, which limits the subsequent processing conditions of flexible thermal devices, such as heat treatment , increasing the complexity of the process;

[0006] 2) The cost of making the electrical connection layer of the thermistor by sputtering is high, and due to the limitation of the sputtering rate, the thickness of the electrical connection layer is generally thin, and a large wire resistance will be introduced during use, and continuous sputtering Wet etching the electrical connection layer after spraying the heat-sensitive film layer and the electrical connection layer may cause corrosion and damage to the heat-sensitive film layer itself;

[0007] 3) Since polyimide has good heat insulation, using polyimide as a protective layer to completely cover the thermistor will reduce the sensitivity of the thermistor to external flow fields or temperature changes

Images