Preparation method of heterogeneous bonding structure

Abstract

The invention provides a preparation method of a heterogeneous bonding structure, which comprises the steps of providing a first substrate and a second substrate, wherein the first substrate is provided with a first bonding surface, the second substrate is provided with a second bonding surface, and the first bonding surface and the second bonding surface are subjected to bonding treatment at a bonding temperature; conducting annealing treatment at an annealing treatment temperature; carrying out cooling treatment to reduce the temperature to a first temperature which is lower than the bondingtemperature; and adjusting the temperature of the structure obtained in the previous step to room temperature so as to obtain a heterogeneous bonding structure formed by the treated first substrate and second substrate. According to the preparation method of the heterogeneous bonding structure, the reinforced structure is cooled to a temperature below the bonding temperature after annealing treatment reinforcement, so that thermal stress opposite to that in the heating process is generated in the cooling treatment process, residual thermal stress in the heterogeneous bonding structure is reduced, and warping of the bonding structure caused by stress can be reduced.

Description

technical field [0001] The invention belongs to the technical field of substrate preparation, in particular to a method for preparing a heterogeneous bonding structure. Background technique [0002] With the development of electronic information technology, devices with a single function have been unable to meet people's needs for device miniaturization and functional diversification. Therefore, the heterogeneous integration of materials or devices with different functions to develop multifunctional integrated electronic modules has become the development direction of electronic technology. For example, NGAS in the United States uses heterogeneous integration technology to integrate InP devices, GaN devices and Si-CMOS devices. Raytheon Corporation of the United States uses heteroepitaxy technology to integrate InP devices with silicon devices. [0003] At present, there are mainly two solutions for heterogeneous integration of different functional materials: heteroepitaxy...

AI Technical Summary

Problems solved by technology

However, due to the large thickness of the wafer used for wafer bonding (generally greater than 200 microns) and the mismatch of thermal expansion coefficients between the heterogeneous materials, the pre-bonded heterogeneous bonded structure will be relatively weak during high temperature annealing. Large thermal stress leads to deformation of the bonding structure

After the bonded structure is cooled to room temperature, the thermal stress generated by post-high temperature annealing cannot be completely released, so there is residual thermal stress inside the heterogeneous bonded structure, resulting in a large warpage of the bonded structure after cooling to room temperature

Since the current wafer processing uses vacuum adsorption or electrostatic adsorption to fix the wafer, the wafer warpage is too large to be adsorbed, so it cannot continue to be used in the subsequent processing technology.

In addition, with the shrinking of micro-nano processing lines in semiconductor technology, large wafer warpage will seriously affect the lithography accuracy of the device structure, thereby reducing the yield of device fabrication and device performance

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