MEMS device vacuum encapsulation method

Abstract

The invention provides a method for vacuum packaging MEMS device by using low temperature co-fired ceramic substrate, comprising the following steps: first using the low temperature co-fired ceramic multilayer circuit structure and three-dimensional wiring to fully embed each passive component and transmission line etc. into the substrate dielectric; then bonding or welding the MEMS device onto the substrate and finishing the electrical connection; finally gaining the vacuum packaging for MEMS device by directly taking the integration of low temperature co-fired ceramic substrate with MEMS device as the base of the package, the metal package for traditional hybrid integrated circuit as the cap, and combining with traditional sealing methods, such as laser seal, land seal and metal tube seal. The technology conditions of the method has advantages of simple to realize, low in cost and easy to batch processes, and realizes vacuum seal for leads, greatly reduces leak bias rate, increases vacuum lifetime performance, particularly applicable to vacuum packaging for application of radio frequency / microwave and inert etc. oriented MEMS devices.

Description

technical field [0001] The invention belongs to the field of micro-electro-mechanical systems, and in particular relates to a method for vacuum packaging MEMS devices such as radio frequency, microwave and wireless communication. Background technique [0002] MEMS (Micro-Electro-Mechanical Systems) technology is a multidisciplinary emerging technology field developed on the basis of microelectronics technology, involving conventional integrated circuit design / process technology and micro-mechanical expertise as well as physics, biochemistry, automatic control, integrated circuits Its research object is a micro-device or system that integrates micro-mechanisms, micro-sensors, micro-actuators, and signal processing / control circuits, interfaces, communications, and power supplies. MEMS devices are low-cost, full-featured, small in size, light in weight, mechanically flexible, low in power consumption, high in reliability, and excellent in performance. They have been widely used...

AI Technical Summary

Problems solved by technology

The main problems are: 1) the transmission of electrical signals to the outside world needs to pass through a very thick structural layer, and the corresponding through hole processing and filling are difficult, or, 2) when the electrode leads are made on the surface of the silicon wafer processed with devices , When communicating with the outside world, thick metal electrodes will make it difficult to control the bonding quality and gas leakage rate; 3) The distribution of device interconnections is mainly single-layer, and the electrical interconnection flexibility is poor; 4) When a certain micro-mechanical structure needs to be connected with When micro-mechanical structures processed on integrated circuit chips or other substrates are integrated in a package, it is difficult to ensure the smooth implementation of the package; 5) The control of the vacuum degree of each device package can only be controlled by vacuum packaging equipment, not The vacuum degree is fine-tuned according to the working characteristics of a single device. In addition, after the packaging process is completed, it is difficult to detect the ability to maintain the vacuum degree.

At present, the use of low temperature co-fired ceramics for MEMS vacuum packaging has not been reported

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