Substrate Dicing by Laser Reforming Region Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor dicing methods, particularly those using laser cutting, often result in inaccuracies and damage to the substrate due to the formation of cracks, which affect the precision and reliability of the dicing process.
Innovation Solution
A method and apparatus that utilize a laser beam to form a reforming region within a substrate by setting target conditions based on sample conditions, ensuring accurate formation of a condensing point on the substrate's surface, thereby minimizing damage and improving dicing accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a laser beam is condensed inside the wafer to cut it, then the dicing process can be performed, but cracks occur in the portion where the laser beam is condensed
Solution Approach 1:
The method performs preliminary characterization on a sample substrate to determine optimal laser parameters before processing the target substrate. This preliminary action includes measuring the relationship between laser power, focal position, and reforming region formation, then using this information to set appropriate parameters for the actual dicing process, preventing crack formation beforehand
Solution Approach 2:
The invention replaces traditional mechanical dicing methods with laser-based reforming region formation. Instead of using physical blades that cause mechanical stress and cracks, the system uses controlled laser irradiation to create reforming regions that guide crack propagation along desired paths without damaging the wafer structure
2Productivity
If the laser beam is condensed to form cracks for cutting, then the wafer can be divided, but the accuracy of the cut is reduced due to crack formation
Solution Approach 1:
The system incorporates feedback mechanisms where the reforming region formation process is monitored and adjusted. Laser parameters such as power, pulse duration, and focal position are optimized based on observed reforming region characteristics, ensuring precise control over where cracks propagate and improving cut accuracy
Solution Approach 2:
The invention systematically varies laser parameters (power, pulse width, repetition rate, focal depth) to optimize the reforming region formation. By changing these parameters based on material properties and desired cut characteristics, the system achieves both effective wafer division and high cutting precision without unwanted crack formation
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 method and apparatus enhance the accuracy and precision of substrate dicing by accurately forming a reforming region, reducing the likelihood of cracks and improving the overall dicing process, allowing for more reliable separation of semiconductor chips.
Implementation Method 1
a stealth dicing method which condenses the laser beam inside the wafer
Implementation Method 2
irradiating a laser beam to a first sample substrate... irradiating the target substrate with the laser beam to form the first reforming region
Data Source
AI summary
A method for dicing a substrate includes setting a target height for forming a first reforming region inside a target substrate, the target height being a distance from an upper surface of the target substrate to the first reforming region; irradiating a laser beam to a first sample substrate including a first film and a second film being in contact with the first film, and setting a target condition on the basis of a sample condition that results in forming a condensing point of the laser beam on an upper surface of the first film being in contact with the second film; and irradiating the target substrate with the laser beam according to the target condition to form the first reforming region inside the target substrate, wherein a thickness of the second film is the target height.