Hexagonal Light Emitting Element Cleavage via Laser Modified Region
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In manufacturing light emitting elements, the cleaving process often deviates from the planned cleavage line, leading to defects and a reduction in yield, especially when producing hexagonal-shaped elements.
Innovation Solution
A method involving a sapphire substrate with a semiconductor layered body, where a laser beam forms a modified region with cracks reaching both main surfaces, followed by CO2 laser irradiation to enhance cleavage along the planned line, ensuring accurate separation of light emitting elements without deviation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a laser beam is used to form a modified region in the substrate, then cleavage can be initiated, but the cleavage deviates from the planned cleavage line resulting in shape defects
Solution Approach 1:
The patent applies preliminary action by first forming a modified region with initial laser irradiation to create cracks reaching both surfaces, then subsequently irradiating with CO2 laser to guide the cleavage along the planned line. This two-stage preliminary preparation ensures the cleavage follows the intended path without deviation, solving the precision problem.
Solution Approach 2:
The modified region acts as an intermediary structure between the laser irradiation and the final cleavage. By creating this intermediate modified region with specific crack patterns, the patent enables controlled cleavage along the planned line, mediating between the energy input and the desired precise separation.
2Productivity
If multiple laser irradiation steps are applied to improve cleavage precision, then manufacturing complexity increases, but yield improves
Solution Approach 1:
The laser irradiation process is segmented into two distinct stages: first forming a modified region with initial laser to create surface-reaching cracks, then using CO2 laser irradiation to guide cleavage along the planned line. This segmentation allows each step to perform its specific function optimally, improving overall yield despite increased process steps.
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
This approach significantly improves the yield of hexagonal light emitting elements by ensuring precise cleavage along the planned line, reducing defects and enhancing manufacturing efficiency.
Implementation Method 1
irradiating a laser beam into the substrate to form a modified region inside the substrate, the modified region having a crack reaching the first main surface and a crack reaching the second main surface
Implementation Method 2
irradiating CO2 laser to a region of the substrate overlapping with a region to which the laser beam has been irradiated
Data Source
AI summary
A method of manufacturing light emitting elements includes: providing a wafer including a substrate formed of sapphire and having a first main surface and a second main surface, and a semiconductor layered body disposed on the first main surface of the substrate; irradiating a laser beam into the substrate to form a modified region inside the substrate, the modified region having a crack reaching the first main surface and a crack reaching the second main surface; irradiating CO2 laser to a region of the substrate overlapping with a region to which the laser beam has been irradiated; and cleaving the wafer along the modified region to obtain the light emitting elements each having a hexagonal shape in a plan view.