Wafer-level encapsulation structure for radio frequency micro-electro mechanical system and encapsulation method thereof

Abstract

The invention relates to a wafer-level encapsulation structure for radio frequency micro-electro mechanical system and an encapsulation method thereof. The wafer-level encapsulation structure comprises a substrate, a microwave transmission layer and an electrical connecting layer are distributed on the substrate; the microwave transmission layer is connected with a radio frequency micro-electro mechanical system device; the substrate is bound with an encapsulation head cover through an organic material encapsulation area and an inorganic material encapsulation area; an encapsulation cavity is formed in the encapsulation head cover; the radio frequency micro-electro mechanical system device is arranged in the encapsulation cavity; the microwave transmission layer passes through the organic material encapsulation area, and an electrical connecting line draws out from the inorganic material encapsulation area. Therefore, the encapsulation structure avoids a traditional substrate through hole punching process, a simple process is used for drawing out a radio frequency signal from the organic material through a microwave transmission line; the existent inorganic material encapsulation area makes up the problem of insufficient air tightness and binding strength when only the organic material encapsulation is existent. The structure disclosed by the invention can effectively guarantee that movable structure part of the radio frequency micro-electro mechanical system device is protected, and the reliability of the radio frequency micro-electro mechanical system device is improved.

Description

technical field [0001] The invention relates to a wafer-level packaging structure and a packaging method thereof, in particular to a wafer-level packaging structure and a packaging method for radio frequency micro-electromechanical systems. Background technique [0002] RF MEMS is an organic combination of microwave radio frequency theory and micromachining technology. Guided by microwave radio frequency theory, it uses microelectronic surface processing and body processing to manufacture passive devices. Compared with traditional passive devices, RF MEMS devices not only have excellent microwave performance such as high isolation, low loss, high linearity, low power consumption, and wide frequency band, but also have mass production, small size, easy and advanced The characteristics of microwave radio frequency circuit integration. [0003] Due to the rapid development of RF MEMS devices in recent years, the research on the packaging of RF MEMS devices has also made great ...

AI Technical Summary

Problems solved by technology

First of all, the micro-electromechanical system (MEMS) process has its complexity, and the packaging process must be compatible with the MEMS process; secondly, because it has movable parts, it needs a stable environment for protection; thirdly, RF MEMS devices are subject to Moisture and pollution have a great influence, so hermetic or near-hermetic hermetic packaging must be used, and the packaging process must also be carried out in an inert gas environment; finally, the interconnection of radio frequency signals is a problem that needs to be studied, because the packaging itself May affect the electrical performance of the switch

In order to lead out the radio frequency signal, there are currently mainly solutions for punching through the substrate and packaging with organic materials, but they have problems such as complex process and insufficient airtightness respectively.

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