MEMS microphone package and packaging method

Abstract

The present invention relates to a MEMS microphone package having improved acoustic properties, and to a packaging method, which involve adding a vent path in the packaging process to improve equilibrium between internal and external air pressure. The MEMS microphone package of the present invention comprises: a MEMS microphone chip having a back plate and a diaphragm formed on a silicon body using MEMS fabrication technology; a substrate on which the MEMS microphone chip is mounted; a bonded portion formed by applying an adhesive onto the substrate excluding one portion, and then bonding the MEMS microphone chip body to the substrate, so as to form a vent path between the MEMS microphone chip body and the substrate; and a case bonded to the substrate so as to define a space for housing the MEMS microphone chip. Equilibrium between internal and external air pressure of the MEMS microphone chip is achieved by means of the vent path, thereby improving acoustic properties.

Description

technical field [0001] The present invention relates to a kind of microelectromechanical system (MEMS) microphone assembly, more particularly about improving the balance (Air equilibrium) of internal air pressure and external air pressure (Air equilibrium) by adding vent path (vent path) during assembly process, thereby Microelectromechanical system microphone assembly and method of assembly for improved acoustic characteristics. Background technique [0002] Since 1980, after research on MEMS microphones was reported by R. Hijab et al., research on various microphone structures and manufacturing techniques using MEMS (micro electro machining systems) technology has been carried out. The MEMS (micro electro machining systems) process can manufacture thin films with stable and adjustable physical properties based on semiconductor process technology, and because it can be mass-produced, it can realize small and low-cost high-performance microphone chips. In addition, compared...

AI Technical Summary

Problems solved by technology

[0005] In the manufacture of microelectromechanical system (MEMS) microphone chips, in order to maintain the balance of internal air pressure and external air pressure (Air equilibrium), vent holes (vent holes) are formed on the vibrating membrane, but due to limited manufacturing technology, when vibrating When the number of exhaust holes on the membrane is large or the diameter is large, the capacitance formed by the area of ​​the support plate and the diaphragm becomes small, so there are problems of reduced sensitivity and low frequency band characteristics. When the exhaust on the diaphragm When the number of holes is small or the diameter is small, although the sensitivity of the vibrating membrane becomes higher, air resistance is generated in the back cavity due to insufficient air equilibrium (Air equilibrium), and there is a problem of abnormal response speed and sensitivity.

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