Microphone packaging structure and forming method thereof

Abstract

The invention relates to a microphone packaging structure and a forming method thereof, and the microphone packaging structure comprises a substrate, and a first concave part is formed on the surfaceof the substrate; a packaging shell which is fixed on the surface of the substrate, and a first cavity is formed between the packaging shell and the substrate; a microphone chip which is arranged in the first cavity, wherein the microphone chip comprises a pressure sensing layer and a supporting structure. And a second cavity is formed between the supporting structure and the pressure sensing layer, the top of the supporting structure supports the pressure sensing layer, and the bottom of the supporting structure is fixed to the surface of the substrate, so that the second cavity communicateswith the first concave part, and the first concave part is located in the projection of the second cavity on the surface of the substrate. The acoustic performance of the microphone chip of the microphone packaging structure is not affected by the packaging process.

Description

technical field [0001] The invention relates to the technical field of MEMS, in particular to a microphone packaging structure and a forming method thereof. Background technique [0002] In the prior art, in the packaging structure of the MEMS microphone, the MEMS microphone is usually solidified and connected to the substrate through glue. In the large-scale manufacturing process, due to the uneven dispensing amount of the machine, when the MEMS microphone is pasted on the substrate and squeezed with the colloid, the colloid will often overflow to the inner and outer sides of the side wall of the MEMS microphone. Excessive colloid When part of it overflows into the cavity of the MEMS microphone, the cavity of the MEMS microphone is usually too small, which affects its acoustic performance and leads to an increase in the failure rate of the product. [0003] In the prior art, the inner side wall of the MEMS microphone cavity is changed from smooth etching to rough surface, ...

AI Technical Summary

Problems solved by technology

In the large-scale manufacturing process, due to the uneven dispensing amount of the machine, when the MEMS microphone is pasted on the substrate and squeezed with the colloid, the colloid will often overflow to the inner and outer sides of the side wall of the MEMS microphone. Excessive colloid When part of it overflows into the cavity of the MEMS microphone, it usually causes the cavity of the MEMS microphone to be too small, which affects its acoustic performance and leads to an increase in the failure rate of the product

[0003] In the prior art, the inner side wall of the MEMS microphone cavity is changed from smooth etching to a rough surface, so as to reduce the impact of colloid overflow on the MEMS microphone cavity, but in fact, the effect of this solution is not very ideal, because the MEMS microphone The cavity itself is very small, even if the colloid does not climb up along the side wall, it still exists in the inner space of the cavity, resulting in a smaller cavity volume, which still has a great impact on the acoustic performance

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