CMOS-MEMS double-sided integrated chip and integration method thereof

Abstract

The invention discloses a CMOS-MEMS double-sided integrated chip and an integration method thereof. The CMOS-MEMS double-sided integrated chip comprises a substrate, a CMOS circuit, an MEMS structureand a metal via hole used for leading a lead wire bonding pad of the CMOS circuit to the surface where the MEMS structure is located, wherein the CMOS circuit and the lead wire bonding pad of the CMOScircuit are attached to the first surface of the substrate, the MEMS structure and the lead wire bonding pad of the MEMS structure are attached to the second surface of the substrate, the first surface and the second surface are oppositely distributed, the metal via hole penetrates through the substrate and is communicated with the first surface and the second surface of the substrate, the lead wire bonding pad of the CMOS circuit is located at the position where the metal via hole is located and electrically connected with the metal via hole, and the metal via hole is electrically connectedwith the lead wire bonding pad of the MEMS structure. According to the invention, the CMOS-MEMS double-sided integrated chip has the advantages that CMOS-MEMS double-sided integration and circuit interconnection after double-sided integration are achieved.

Description

technical field [0001] The invention relates to the technical field of micro-electromechanical systems, and more specifically to a CMOS-MEMS double-sided integrated chip and an integration method thereof. Background technique [0002] Micro-Electro-Mechanical Systems (MEMS, Micro-Electro-Mechanical System), also known as micro-electro-mechanical systems, micro-systems, micro-machines, etc., refers to high-tech devices with a size of a few millimeters or even smaller. MEMS is an independent intelligent system whose internal structure is generally on the order of microns or even nanometers. MEMS is developed on the basis of microelectronics technology (semiconductor manufacturing technology), and integrates high-tech electronic machinery produced by technologies such as lithography, corrosion, thin film, LIGA, silicon micromachining, non-silicon micromachining and precision machining. device. MEMS is a revolutionary new technology, widely used in high-tech industries, and a ...

AI Technical Summary

Problems solved by technology

However, many sensors with MEMS structures have complex structures, require high-temperature processes, wet etching processes, etc., or produce films with high stress. Such processes are difficult to be compatible with CMOS processes. CMOS and MEMS monolithic integration processes are still a huge challenge. challenge

[0004] At present, CMOS-MEMS monolithic integration in the world usually separates the CMOS and MEMS processes, that is, the CMOS process and the MEMS process are carried out separately. In terms of structure, the CMOS or MEMS process is first completed on the side of the silicon base, leaving another process. The required space is to carry out the next process after the previous process is completed. Although this process achieves the monolithic integration of CMOS and MEMS to a certain extent, the area of ​​the chip will increase a lot

[0005] In order to further solve the problem of increasing the chip area caused by CMOS-MEMS monolithic integration, in recent years, there are patents such as Chinese Patent Publication No. CN108840307A, which propose a method for monolithically integrating CMOS circuits and bulk silicon MEMS, using SOI silicon chips First, make a CMOS circuit on the substrate surface layer of the SOI silicon wafer, and then protect it with an insulating layer to make a MEMS structure on the SOI silicon wafer structure layer

However, this method does not solve the problem of interconnection between CMOS and MEMS circuits, and because the SOI silicon wafer structure layer is usually very thin, it is difficult to complete many MEMS structures that require deep grooves

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