Direct Bonding Tool with Integrated Laser Surface Cleaning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor surface cleaning techniques are inadequate for removing micron and submicron-sized particles, which can lead to circuit failure and yield loss, and are often time-consuming and prone to re-contamination during the transition from cleaning to bonding processes.
Innovation Solution
Integration of a laser cleaning assembly with the bonding tool, utilizing laser-induced shock waves or direct irradiation to effectively remove particles and organic residue from semiconductor surfaces, reducing the need for additional cleaning steps and minimizing re-contamination risks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If traditional cleaning techniques (high-pressure gas jet, scrubbing, ultrasonic, chemical flux) are used, then particles can be removed from semiconductor surfaces, but post-cleaning rinse steps and surface drying time are required, increasing processing time
Solution Approach 1:
The patent replaces mechanical cleaning systems (high-pressure gas jets, scrubbing brushes, ultrasonic vibrations) with a laser-based cleaning system. The laser beam directly ablates particles from the semiconductor surface through photothermal and photomechanical effects, eliminating the need for mechanical contact and subsequent rinse/dry steps, thus reducing total processing time while maintaining cleaning effectiveness
Solution Approach 2:
The laser cleaning process utilizes phase transitions of material. The laser energy causes rapid heating and vaporization of particles and contaminated layers on the semiconductor surface. This phase change from solid particle to gas/vapor enables complete removal without residue, eliminating the need for chemical flux and rinse steps required by traditional methods
2Manufacturing precision
If traditional cleaning techniques are used, then cleaning can be performed, but delays between cleaning and bonding occur, allowing re-contamination that affects yield
Solution Approach 1:
The patent merges the cleaning process and bonding process into a single integrated tool. The laser cleaning assembly is positioned within the bonding tool, allowing cleaning to be performed immediately before bonding without transferring the wafer to a separate cleaning tool. This eliminates delays and handling steps that could cause re-contamination, thereby improving bonding yield while maintaining surface cleanliness
Solution Approach 2:
The laser cleaning is performed as a preliminary action immediately before bonding within the same tool. The cleaning process prepares the surface right at the bonding station, ensuring the surface remains clean throughout the bonding operation. This preliminary cleaning action is timed to occur just moments before bonding, preventing re-contamination that would occur with delays between separate cleaning and bonding operations
3Extent of automation
If robotic handling is used to transfer wafers, then automation is achieved, but handling time increases the risk of re-contamination
Solution Approach 1:
The patent combines the robotic handling function with the laser cleaning function in a single integrated tool. The robotic arm performs both wafer transfer and laser cleaning operations without requiring separate handling steps. This merging eliminates additional handling time and exposure to contamination risks while maintaining full automation, thereby improving contamination control without sacrificing automation level
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
The laser cleaning method provides a rapid, effective means of removing nanoscale to microscale particles without the use of chemical agents, reducing processing time and re-contamination, thereby enhancing the yield and reliability of direct bonding processes.
Implementation Method 1
utilizing laser-induced shock waves or direct irradiation to effectively remove particles and organic residue from semiconductor surfaces
Implementation Method 2
utilizing laser-induced shock waves or direct irradiation to effectively remove particles and organic residue from semiconductor surfaces
Data Source
AI summary
Bonding tools and related systems are provided for surface cleaning and direct bonding. A bonding tool includes a support configured to hold a first element, and is further configured to bond a second element to the first element by way of direct bonding. A laser cleaning assembly is configured to clean the first and/or second element prior to bonding, and can be integrated with the bonding tool. The laser cleaning can also clean surfaces of the bonding tool and/or a robotic end effector for delivering the second element. Methods and sequences for surface cleaning and direct bonding using the systems are also disclosed.