A kind of temperature and humidity sensor for refrigerated transport vehicle and preparation method thereof

Abstract

The invention relates to a temperature and humidity sensor of a refrigerated transport carrier and a producing method thereof. A temperature-sensing unit and a humidity-sensing unit of the sensor are respectively fixedly installed in a corresponding square groove produced by a silicon nitride passivation layer. The producing method comprises steps: depositing a thick silicon nitride passivation layer; photoetching and corroding the thick silicon nitride passivation layer to form two chambers used as separating chambers of the temperature-sensing unit and the humidity-sensing unit; installing the temperature-sensing unit and the humidity-sensing unit in a corresponding separating chamber respectively; printing and installing a peripheral processing circuit; and finally packaging and the detecting the whole sensor. The top electrode, the bottom electrode, and the humidity-sensing film of the humidity-sensing unit all use comb-shaped structure. The use of the comb-shaped structure of the electrodes is advantageous in that the capacitance output value of the humidity-sensing unit can be increased. The use of the comb-shaped structure of the humidity-sensing film is advantageous in that the contact area between the film and air is enlarged such that time of water molecules entering and existing the humidity-sensing film is shortened and further the response speed of the sensor is increased. The temperature and humidity sensor is produced by using CMOS technology and has characteristics of microminiaturization and low power consumption.

Description

technical field [0001] The invention belongs to the field of transportation, and relates to a temperature and humidity sensor used in a refrigerated transportation vehicle, in particular to a temperature and humidity sensor for a refrigerated transportation vehicle prepared by a CMOS process and a preparation method thereof. Background technique [0002] Agriculture belongs to the primary industry. The preservation and processing of agricultural products is the continuation of agricultural production. All developed countries put post-production storage and processing at the top of agriculture. With the improvement of economic globalization, the refrigerated transportation industry is developing rapidly. During the transportation process, it is particularly important to ensure the transportation safety of fresh and live goods, and solving this problem will bring huge economic benefits. Therefore, high-precision monitoring of the environment inside the refrigerated transport v...

AI Technical Summary

Problems solved by technology

[0005] Most of the existing NTC chips use epoxy resin or phenolic resin as the insulating protective layer. The dipping process determines that its thickness cannot be very thin, so it will affect the accuracy of temperature measurement and the response speed of the sensor.

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