Capacitance type micro mechanical temperature sensor for multi-layer beam structure

Abstract

The multi-layered structure electric capacity type temperature sensor is composed of the electric capacity pole plate and the connection electric capacity pole plate's lead wire. It is made using the micro machine-finishing method. This sensor is composed of the upper electric capacity pole plate(1), the under electric capacity pole plate (2) ,and the first lead wire (3) and the second lead wire (4) connecting the electric capacity pole plate. The electric capacity pole plate (1) and the under electric capacity pole plate (2) is the conductive coating, between them is full of the isolation medium membrane (5) packing. The first lead wire (3) and the second lead wire (4) corresponds separately with the previous electric capacity pole plate (1) and the under electric capacity pole plate (2) docking. The electric capacity pole plate (2) is located in the substrate on (6), under which is equipped with the cavity. The conductive coating on the electric capacity pole plate (1) is the metallic membrane, while the plate (2) is the P+ level, and the isolation medium membrane (5) is the silicon dioxide. When the temperature changes, the multi-layer each material has the thermal load because of the thermal-expansion coefficient unbalance, causing the multi-layered to bend deformation and the sensor electric capacity changing.

Description

technical field [0001] The invention relates to a micromechanical temperature sensor, in particular to a capacitive temperature sensor with a multi-layer beam structure. Background technique [0002] Temperature sensors are one of the most commonly used sensors in the process of industrial and agricultural production and scientific research. There are many types, which can be roughly divided into traditional discrete sensors and semiconductor temperature sensors. Although traditional temperature sensors (such as thermocouples, platinum resistors, bimetallic switches, etc.) have their own irreplaceable advantages, their large size and poor consistency restrict their application in miniaturized high-end electronic products. The semiconductor temperature sensor has many advantages such as high sensitivity, small size, low power consumption, small time constant, small self-heating temperature rise, and strong anti-interference ability. Both have a linear relationship with tempe...

AI Technical Summary

Problems solved by technology

Although traditional temperature sensors (such as thermocouples, platinum resistors, bimetallic switches, etc.) have their own irreplaceable advantages, they are large in size and poor in consistency, which restricts their application in miniaturized high-end electronic products

The semiconductor temperature sensor has many advantages such as high sensitivity, small size, low power consumption, small time constant, small self-heating temperature rise, and strong anti-interference ability. Both have a linear relationship with temperature, but due to the existence of PN junctions, their applications in harsh environments (such as high temperature, low temperature, radiation) are limited

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