Wafer Alignment Using Multi-Mark Die Handler Registration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bonding techniques for semiconductor devices face challenges in achieving high-order alignment and positioning, particularly in die-to-wafer bonding processes, leading to potential misalignment issues that are critical as feature sizes continue to decrease.
Innovation Solution
A method and apparatus that involves aligning a die with a die handler using multiple alignment marks, followed by aligning the die handler with a target substrate, utilizing a substrate stage and alignment detection module to enhance alignment accuracy, and then bonding the die to the target substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional bonding techniques are used for die-to-wafer bonding, then the bonding process can be completed, but alignment accuracy is insufficient leading to misalignment issues
Solution Approach 1:
The alignment process is segmented into multiple hierarchical levels: first aligning the carrier substrate to the die handler using carrier alignment marks and die handler alignment marks, then aligning the die to the target substrate using die alignment marks and substrate alignment marks. This multi-stage segmentation enables higher overall alignment accuracy by breaking down the complex alignment task into manageable steps, each contributing to the final positioning precision.
Solution Approach 2:
The die handler serves as an intermediary component with its own alignment marks that mediate between the carrier substrate and the target substrate. By introducing this intermediate alignment reference, the system achieves better overall alignment accuracy than direct bonding would allow, as the die handler acts as a stable reference frame for both the die and the substrate positioning.
2Manufacturing precision
If feature sizes are reduced to continue miniaturization, then integration density increases, but alignment precision requirements become more stringent
Solution Approach 1:
Alignment marks are pre-defined and pre-positioned on the carrier substrate, die handler, die, and target substrate before the bonding process. This preliminary preparation of reference markers enables accurate alignment to be achieved without requiring complex real-time measurement and adjustment systems, thus maintaining process simplicity while meeting stringent alignment precision requirements for miniaturized features.
Solution Approach 2:
Multiple identical alignment marks are placed at different locations on each component (carrier substrate, die handler, die, and target substrate). These replicated reference markers provide redundant alignment references that improve measurement accuracy and enable verification of alignment quality, ensuring high precision bonding even as feature sizes decrease and tolerance windows narrow.
Data Source
AI summary
A method includes providing a carrier substrate having a die bonded thereto, where the die includes a first alignment mark on a first surface. The method includes positioning a target substrate with a second surface on a substrate stage, where the target substrate includes a second alignment mark on the second surface. The method includes positioning the carrier substrate with respect to a die handler, where the die handler includes a third alignment mark. The method includes coupling the die to the die handler, where the step of coupling includes aligning the first alignment mark with the third alignment mark. The method includes positioning the coupled die and the die handler over the target substrate, where the step of positioning includes aligning the second alignment mark with at least one of the first alignment mark and the third alignment mark. The method includes bonding the first surface with the second surface.