Laser Wafer Dicing for Precise Chip Thickness Without Grinding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for producing chips from wafers lack the ability to efficiently produce chips of desired thicknesses, often requiring multiple steps and equipment like grinding apparatuses, which are costly and inefficient.
Innovation Solution
A method involving laser processing to form grooves and separation initiating points on wafers, allowing for the precise peeling of chips of varying thicknesses without the need for grinding, using a focused laser beam to create modified layers and cracks that facilitate chip separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional grinding and cutting methods are used to produce chips from wafers, then chips of desired thickness can be produced, but multiple steps and equipment (including grinding apparatuses) are required, increasing cost and installation space
Solution Approach 1:
The patent combines groove forming, separation initiating point formation, and chip peeling into a single integrated laser processing apparatus that performs all operations in one device, eliminating the need for separate grinding apparatuses and multiple processing steps while maintaining precise chip thickness control
Solution Approach 2:
The laser processing apparatus is designed to perform multiple functions: forming grooves to specified depths, creating separation initiating points through focused laser beams, and enabling chip peeling, thereby replacing multiple specialized equipment with a single multi-functional device
2Manufacturing precision
If multiple processing steps and equipment are used, then chips of desired thickness can be produced, but processing time and production efficiency are reduced
Solution Approach 1:
The laser processing apparatus performs preliminary groove forming to the exact depth corresponding to the desired chip thickness before creating separation initiating points, ensuring that chip peeling occurs precisely at the intended location and depth, thereby achieving both precision and efficiency in a single integrated process
Solution Approach 2:
The patent implements continuous laser processing where the focused laser beam continuously forms grooves and separation initiating points along the wafer surface without interruption, eliminating the need for multiple discrete processing steps and equipment changes, thereby maintaining continuous productive action throughout the chip production process
3Ease of manufacture
If conventional methods are used, then chip separation can be achieved, but additional steps to lower adhesive tape power are required, increasing process complexity
Solution Approach 1:
The patent replaces mechanical chip separation methods that require adjusting adhesive tape power with a laser-based system that forms separation initiating points through optical energy, eliminating the need for mechanical adjustment steps and simplifying the overall manufacturing process while maintaining effective chip separation
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
Enables the efficient production of chips with desired thicknesses using a single laser processing apparatus, reducing costs and installation space, and eliminating the need for additional steps to lower adhesive tape power, while preventing chip damage and improving processing efficiency.
Implementation Method 1
forming grooves in the wafer to a depth equal to or larger than a desired thickness of the chips from the face side of the wafer along the projected dicing lines
Implementation Method 2
positioning a focused spot of a laser beam having a wavelength transmittable through the wafer, at a depth in the wafer corresponding to a thickness of the chips from a reverse side of the wafer that is opposite the face side thereof, applying the laser beam to the wafer while moving the focused spot and the wafer relatively to each other, thereby forming separation initiating points in the wafer that are parallel to the face side of the wafer and made up of modified layers and cracks extending from the modified layers
Data Source
AI summary
A method of processing a wafer includes a groove forming step of forming grooves in the wafer to a depth equal to or larger than a thickness of chips to be produced from the wafer from a face side of the wafer along projected dicing lines, a separation initiating point forming step of positioning a focused spot of a laser at a depth in the wafer corresponding to a thickness of the chips from a reverse side of the wafer, applying the laser beam to the wafer while moving the focused spot and the wafer relatively to each other, thereby forming separation initiating points in the wafer that are parallel to the face side of the wafer and made up of modified layers and cracks, and a chip peeling step of peeling off the chips from the wafer at the separation initiating points.