Thermal type wind sensor based on anisotropic heat-conducting substrate and preparation method therefor

Abstract

The invention discloses a thermal type wind sensor based on an anisotropic heat-conducting substrate; a chip of the sensor comprises the anisotropic heat-conducting substrate; four heating elements are symmetrically distributed at the center of the upper surface of the anisotropic heat-conducting substrate; four thermal sensing temperature-measuring elements are symmetrically distributed at the periphery of the four heating elements; the back surface of the anisotropic heat-conducting substrate is contacted with external environment so as to detect wind speed and wind direction; a glass heat-insulation inner ring is inlaid among the heating elements in the anisotropic heat-conducting substrate and silicon substrates under the thermal sensing temperature-measuring elements; a glass heat-insulation outer ring is inlaid among the silicon substrates under the thermal sensing temperature-measuring elements and silicon substrates at the edge of the chip; the two glass heat-insulation rings can ensure that the thickness of the anisotropic heat-conducting substrate is thinned to be about 100 microns by a thinning technology on one hand, the total power consumption of the sensor can be reduced on the other hand so that the sensor keeps higher signal sensitivity and shorter thermal response time under the lower power consumption.

Description

technical field [0001] The invention relates to a thermal wind speed and direction sensor prepared on an anisotropic thermally conductive substrate structure, in particular to a low power consumption and self-encapsulated wind speed and direction sensor and a preparation method thereof. Background technique [0002] In the design of thermal wind speed and direction sensors, packaging has always been a technical bottleneck hindering its development. On the one hand, the encapsulation material is required to have good thermal conductivity and to protect the sensor, and the impact of the encapsulation material on the sensitivity, reliability and price of the sensor needs to be considered in the design, which limits the sensor’s own encapsulation. Design freedom. On the other hand, the thermal flow sensor requires the sensitive part of the sensor to be exposed to the measurement environment, and at the same time requires the processing circuit to be isolated from the environmen...

AI Technical Summary

Problems solved by technology

As a result, silicon wafers are easily subject to various contaminations, resulting in unstable performance and even damage.

If a ceramic substrate with high thermal conductivity is used, and the silicon chip of the sensor is packaged by flip-chip packaging or thermally conductive adhesive, the above contradictions can be better avoided, but the heat generated by the sensor after packaging is extremely large. Part of it is dissipated from the silicon-based substrate in the form of heat conduction, and only a small part is heat-exchanged with the outside air through the ceramic, which greatly reduces the amplitude of the output sensitive signal, and the sensitive signal can be improved by increasing the power consumption of the sensor. amplitude, but it causes a large power consumption of the entire sensor system

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