Chiplet Bonding Pad Alignment with Planarity Error Compensation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing systems face challenges in accurately aligning bonding pads on chiplets due to variations in shape and planarity, which complicates the bonding process as the size of interconnect contacts decreases and density increases.

Innovation Solution

A method and system that utilize image-based alignment to measure deviations from planarity, estimate chiplet-position errors, and adjust the relative position of chiplets and substrates based on these errors, incorporating processors and sensors to enhance alignment accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If image-based alignment is used to align bonding pads, then alignment speed and automation are improved, but alignment precision deteriorates due to shape variations and non-planarity of chiplet surfaces

Engineering Contradiction:

Improvealignment speedVSAvoidalignment precision

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The system performs preliminary actions by capturing images of the chiplet surface and calculating shape variations (e.g., curvature, warpage) before the alignment process. This pre-characterization of surface geometry allows the system to compensate for non-planarity during alignment, enabling both high speed and high precision by preparing correction data in advance

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system changes parameters by adjusting alignment calculations based on measured shape variations. Instead of assuming a flat surface, the system modifies the alignment transformation parameters to account for captured surface geometry, thereby maintaining precision while using automated image-based methods

Inventive Principle:

Principle #35Parameter changes

2Productivity

If the size of interconnect contacts is reduced and density is increased, then device integration is improved, but alignment difficulty increases due to smaller tolerance margins

Engineering Contradiction:

Improvedevice integrationVSAvoidalignment difficulty

Core Design Contradiction:

ProductivityVSDifficulty of detecting and measuring

Solution Approach 1:

The system replaces mechanical alignment methods with optical/image-based alignment. By using imaging to detect bonding pad positions and calculate transformations, the system achieves sub-micron precision required for small interconnect contacts without relying on mechanical positioning, thereby reducing alignment difficulty despite smaller tolerance margins

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS20250308965A1Systems, devices, and methods for compensating for shape variations when using image-based alignment to align bonding pads

Publication Date: 2025.10.02 CANON KK

AI summary

Some devices, systems, and methods for aligning a chiplet to a substrate obtain an image of a region on a chiplet, measure a deviation from planarity of the region on the chiplet, estimate a chiplet-position error of the chiplet based at least on the image of the region and the deviation from planarity of the region, and adjust a relative position of the chiplet and a substrate based on the chiplet-position error.