Wafer Bonding via Reservoir Reactant Diffusion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for irreversible substrate bonding require high temperatures, leading to energy consumption and potential damage, and fail to ensure compatibility with existing electrically active components, particularly transistors, while also causing thermal stress and contamination.
Innovation Solution
A method involving a reservoir on one substrate that reacts with a second educt on the opposing substrate to form a permanent bond at lower temperatures, using a native oxide material and plasma activation to enhance bonding speed and strength, with a growth layer that minimizes gaps and promotes diffusion, thereby reducing mechanical loading and contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If high temperatures (>400°C) are used for bonding, then bond force and reproducibility are improved, but energy consumption increases and structures on substrates may be destroyed
Solution Approach 1:
The patent applies preliminary action by pre-forming a reservoir containing the first educt (reactant) on one substrate surface before bonding. This reservoir structure, combined with pre-activated surfaces, enables the bonding reaction to proceed at lower temperatures (200-400°C) while achieving sufficient bond force, thereby reducing energy consumption compared to conventional high-temperature bonding methods
2Strength
If high temperatures (>400°C) are used for bonding, then bond force and reproducibility are improved, but active components such as transistors may be damaged
Solution Approach 1:
The patent employs preliminary action by pre-activating the substrate surfaces and pre-forming the reservoir structure before bonding. This preparation enables the bonding reaction to occur at reduced temperatures (200-400°C), which protects temperature-sensitive active components like transistors from thermal damage while still achieving strong, reproducible bonds
Solution Approach 2:
The patent changes the temperature parameter from conventional high temperatures (>400°C) to a lower range (200-400°C) by modifying the bonding process through reservoir formation and surface activation. This parameter change allows sufficient bond strength to be achieved without exposing active components to damaging high temperatures
3Strength
If high temperatures are used for bonding, then bond force is improved, but thermal stress and contamination increase
Solution Approach 1:
The patent applies preliminary action by pre-forming the reservoir and activating surfaces before bonding, enabling the reaction to proceed at lower temperatures. This reduces thermal stress on the substrates and minimizes contamination from high-temperature processes, while still achieving strong bonds through the controlled chemical reaction in the reservoir
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method achieves a strong, irreversible bond at lower temperatures, reducing energy consumption and mechanical stress, while maintaining compatibility with active components and minimizing contamination, thereby increasing bond strength and reliability.
Implementation Method 1
The diffusion rate of the educts through the growth layer is increased by the growth layer, which has been thinned, so that the transport time of the educts is reduced at the same temperature
Implementation Method 2
the reaction of the first educt with the second educt, which is present in the reaction layer of the second substrate, causes the growth layer to grow, as a result of which the pores on the contact surface between the substrates are closed
Data Source
AI summary
This invention relates to a method for bonding of a first contact surface of a first substrate to a second contact surface of a second substrate with the following steps, especially the following sequence:forming a reservoir in a surface layer on the first contact surface, the first surface layer consisting at least largely of a native oxide material,at least partial filling of the reservoir with a first educt or a first group of educts,the first contact surface making contact with the second contact surface for formation of a prebond connection,forming a permanent bond between the first and second contact surface, at least partially strengthened by the reaction of the first educt with a second educt contained in a reaction layer of the second substrate.