Laser Grooving Restriction for Element Chip Dicing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing manufacturing process of element chips using laser-grooving and plasma-etching techniques often damages the holding sheet, leading to insufficient cooling, coolant gas leakage, and anomalous electric discharges due to laser irradiation beyond the substrate edges, causing damage and inefficiencies in the plasma-dicing process.
Innovation Solution
The process involves irradiating the laser beam only within the inner region of the substrate's outer edge during the laser-grooving step, forming shallower grooves that prevent damage to the holding sheet and ensuring efficient plasma-etching by maintaining the substrate's integrity and preventing coolant gas leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the laser beam is irradiated across the whole substrate surface from beyond one outer edge through beyond the other outer edge, then the laser-grooving can be completed along all dicing regions, but the holding sheet is scarred and damaged at the portions beyond the substrate edges
Solution Approach 1:
The laser beam irradiation is selectively applied only to regions inside the outer edge of the substrate, creating a local quality distinction between the irradiated substrate area and the non-irradiated holding sheet area. This prevents the holding sheet from being exposed to harmful laser radiation while still achieving complete grooving along all dicing regions within the substrate boundaries.
Solution Approach 2:
The laser irradiation area is segmented and limited to only the necessary region inside the substrate's outer edge, separating the functional irradiation zone from the non-functional holding sheet area. This segmentation ensures that laser energy is concentrated where needed for grooving while avoiding unnecessary exposure of the holding sheet.
2Productivity
If the holding sheet is irradiated by the laser beam, then the laser-grooving process can be completed, but the stretched and crimped portions of the holding sheet insufficiently cool down during plasma-etching
Solution Approach 1:
The laser irradiation is locally restricted to areas inside the substrate's outer edge, preventing the holding sheet from being exposed to laser heating. This local quality control ensures that the holding sheet maintains its original flat condition and can be efficiently cooled during subsequent plasma-etching processes.
Solution Approach 2:
By preventing laser irradiation of the holding sheet in advance, the patent anticipates and prevents the thermal problems that would occur during plasma-etching. The holding sheet is protected from laser-induced heating before the plasma-etching process begins, ensuring proper cooling functionality.
3Productivity
If the laser beam irradiates beyond the substrate outer edge, then the laser-grooving can be completed, but through-holes are formed in the holding sheet causing coolant gas leakage
Solution Approach 1:
The laser irradiation is precisely localized to regions inside the substrate's outer edge, creating a clear spatial boundary between the grooving zone and the holding sheet. This local quality control prevents through-hole formation in the holding sheet while ensuring complete grooving along all dicing regions within the substrate.
Solution Approach 2:
The processing area is segmented into the substrate region requiring laser grooving and the holding sheet region requiring protection. By limiting laser irradiation to the substrate region only, the patent prevents harmful interactions with the holding sheet that would create through-holes and compromise coolant gas containment.
4Productivity
If the holding sheet is damaged by laser irradiation, then the laser-grooving process can be completed, but anomalous electric discharge occurs in the plasma-dicing apparatus
Solution Approach 1:
The laser irradiation is locally confined to the substrate area inside the outer edge, preventing damage to the holding sheet that would cause anomalous electric discharge during plasma-dicing. This local quality control ensures both complete grooving and stable plasma processing.
Solution Approach 2:
The patent applies preliminary anti-action by preventing laser-induced damage to the holding sheet before the plasma-dicing process. By restricting laser irradiation to the substrate region only, the holding sheet remains intact and free from conditions that would cause anomalous electric discharge, ensuring stable plasma processing.
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 reduces damage to the holding sheet, prevents burning and electric discharges, and enhances the plasma-dicing process by maintaining the substrate's integrity and ensuring efficient coolant management, resulting in improved chip production quality and process reliability.
Implementation Method 1
a first laser-grooving step for forming a plurality of grooves by irradiating a laser beam to the first side of the substrate along the dicing regions
Implementation Method 2
a plasma-dicing step for plasma-etching the substrate along the grooves in depth through a plasma exposure of the substrate
Data Source
AI summary
A manufacturing process of an element chip, comprising a substrate preparing step for preparing a substrate having first and second sides opposed to each other, and including a plurality of dicing regions and element regions defined by the dicing regions, the first side being covered by a protective film, a first laser-grooving step for forming a plurality of grooves by irradiating a laser beam to the first side along the dicing regions, and a plasma-dicing step for plasma-etching the substrate along the grooves in depth through a plasma exposure, thereby to dice the substrate into a plurality of element chips, wherein the second side of the substrate and an annular frame are held on a holding sheet in the substrate preparing step, and wherein the laser beam is irradiated only in a region inside an outer edge of the substrate in the first laser-grooving step.