A self-aligned hybrid bonding structure and a manufacturing method thereof

Abstract

The invention discloses a self-aligned hybrid bonding structure, comprising a self-aligned structure I with an inverted trapezoidal groove III and a self-aligned structure II with a regular trapezoidal second dielectric layer pattern, wherein the inverted trapezoidal groove III and the regular trapezoidal second dielectric layer pattern can be closely bonded; The self-aligned structure I comprisesa metal interconnect structure I, a first dielectric layer located above the metal interconnect structure I, the inverted trapezoidal groove III penetrating the first dielectric layer, and the inverted trapezoidal groove II does not overlap with the metal interconnect layer in the vertical direction; The self-aligned structure II comprises a metal interconnect structure II, a first dielectric layer on the metal interconnect structure II, and a regular trapezoidal second dielectric layer pattern, the regular trapezoidal second dielectric layer pattern being located above the second dielectriclayer. The self-aligned structure II comprises a metal interconnect structure II, a first dielectric layer on the metal interconnect structure II, and a regular trapezoidal second dielectric layer pattern. The invention provides a self-aligned hybrid bonding structure and a manufacturing method thereof, which can improve the alignment accuracy and the bonding quality when the hybrid bonding is performed.

Description

technical field [0001] The invention relates to a hybrid bonding technology, in particular to a self-aligned hybrid bonding structure and a manufacturing method thereof. Background technique [0002] With the development of semiconductor VLSI, the existing technology has approached the physical limit. Driven by the further miniaturization and multi-functionalization of electronic products, other new technologies, new materials, and new technologies have been explored. Three-dimensional stack packaging technology is one of them. The three-dimensional stacked packaging technology stacks silicon wafers through bonding technology to realize a three-dimensional metal interconnection structure, which can reduce the interconnection distance, increase the transmission speed, reduce the device volume, and provide the possibility of heterogeneous structure integration. [0003] Wafer bonding technology is one of the important means to realize three-dimensional stacking. Wafer bondi...

AI Technical Summary

Problems solved by technology

However, in this wafer bonding process with a smooth surface, high-precision metal-to-metal alignment is required during bonding. Since the current optical alignment technology for bonding alignment can only use infrared light sources, the alignment accuracy There is a theoretical limit, and there is usually a counter-rotation error. When the alignment error is large, the metal contact surface is too small, which will make the resistance too high

At the same time, the part where the metal-insulation layer contacts cannot obtain high-strength bonding force, which will reduce the reliability of the overall bonding

Therefore, the current optical alignment technology using infrared light sources can no longer meet the requirements of three-dimensional stacking technology. To further improve the bonding alignment accuracy, other process technologies are needed.

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