Coplanar bonding structure and preparation method thereof

Abstract

The invention provides a coplanar bonding structure and a preparation method thereof. The preparation method comprises the following steps: a, providing a device structure to be bonded, wherein the device structure comprises at least two defined function areas, each function area is provided with a face to be drawn out, and the at least two faces to be drawn out are disposed at planes at different heights; and b, drawing each face to be drawn out to planes at the same height to form each bonding drawn-out face so as to obtain the coplanar bonding structure through a lamination structured alternatively formed by an insulation layer and a metal layer. According to the invention, the coplanar bonding structure can solves the problem that the bonding planes in vacuum or air-tight packaging are not at the same height; the internal structure of the vacuum or air-tight packaging is directly vertically interconnected with the outside of the device; and electrical conduction of insulation and lead wire pads of a bonding frame is realized. The coplanar bonding structure only requires to modify patterns at corresponding positions of masks and does not require additional operation procedures, thereby greatly saving the manufacturing cost and improving the production efficiency.

Description

Technical field [0001] The invention relates to the field of micro-electromechanical systems and packaging, in particular to a coplanar bonding structure and a preparation method thereof. Background technique [0002] Micro Electro Mechanical System (MEMS) is a micro device or system that integrates micro mechanisms, micro sensors, micro actuators, signal processing and control circuits, up to interface, communication and power supply. MEMS technology is developing into a huge industry. However, to realize the commercialization and marketization of MEMS requires more in-depth and systematic research on MEMS packaging. The packaging form of MEMS products is a key factor in bringing them to the market successfully, as well as a key factor in MEMS design and manufacturing. The best packaging can enable MEMS products to perform their due functions. The main function of MEMS device packaging is to provide mechanical support and environmental protection for the chip to avoid damage an...

AI Technical Summary

Problems solved by technology

At present, both Through Silicon Via (TSV) and Through-wafer Interconnects (TWI) are effective ways to realize the vertical interconnection of 3D stacked chips. However, at the wafer level, these two technologies However, it is difficult to achieve simultaneous bonding of the bonding frame of the device vacuum or hermetic package and the pad of the electrical interconnection with the package cap, because there is a problem of coplanar bonding in the wafer-level bonding process

[0004] In fact, after the silicon wafer has gone through multiple repeated semiconductor manufacturing processes, its functional areas (such as the movable structure, the lead pads of the two functional areas of the support structure, and the functional area of ​​the bonding frame, etc.) are no longer on the same plane. In 3D packaging, it is often necessary to realize the vertical extraction of signals from the lead pads through bonding. Since the plane of the bonding frame is often lower than the plane of the lead pads at this time, when ensuring the reliable connection of the bonding frame (such as vacuum or Hermetic package) is easy to cause mechanical damage or even damage to the lead pads, or in order to achieve the electrical vertical interconnection of the lead pads, the reliable connection of the bonding frame cannot be guaranteed

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