Direct Chip Bonding for Thin High-Throughput Stacking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current chip-to-wafer and chip-to-chip bonding processes using solder balls or copper pillars result in increased chip thickness and require additional materials, limiting throughput and performance.
Innovation Solution
A direct bonding method and device that eliminates the need for solder balls or copper pillars by using a direct bond, such as a metal-to-metal solid-state bond, which is performed at low temperatures without a liquid phase, ensuring high bond strength and cleanliness of the bonding surfaces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional bonding methods (e.g., eutectic bonding, anodic bonding, fusion bonding) are used to bond chips to substrates, then bonding strength can be achieved, but the process becomes complex, time-consuming, and requires specialized equipment and cleanroom environments
Solution Approach 1:
The patent replaces complex thermal and chemical bonding processes with a mechanical bonding approach. A recess is formed in the substrate, and the chip is mechanically inserted and retained within this recess structure, eliminating the need for eutectic bonding, anodic bonding, or fusion bonding equipment and processes.
Solution Approach 2:
The substrate is segmented by forming a recess that creates a physical cavity. This recess structure divides the bonding interface into distinct regions: the chip seating area within the recess and the surrounding substrate surface, allowing for simplified mechanical retention without complex bonding processes.
2Reliability
If conventional bonding processes are used, then chips can be bonded to substrates, but the bonding process takes a long time and reduces manufacturing productivity
Solution Approach 1:
The recess is pre-formed in the substrate before chip attachment. This preliminary structural preparation allows for direct mechanical insertion and retention of the chip, eliminating the need for time-consuming bonding processes during the assembly stage and significantly improving manufacturing productivity.
3Strength
If conventional bonding methods are used, then chips can be attached to substrates, but the process requires specialized equipment and cleanroom environments, increasing manufacturing cost
Solution Approach 1:
The patent substitutes mechanical retention through recess formation with conventional thermal/chemical bonding methods. This mechanical approach can be implemented with standard manufacturing equipment without requiring specialized bonding equipment or controlled cleanroom environments, thereby reducing manufacturing costs and improving ease of manufacture.
Data Source
Figure 1a~1g
Figure 2a~2e
Figure 2f~4
AI summary
The invention relates to a method for bonding chips (7) to a substrate (11') or to further chips, characterized in that the chips (7) are bonded by a direct bond to the substrate (11') or to the further chips.