Wafer Processing Using Adhesive Tape for Chip Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The 'dicing before grinding' method for semiconductor device chip production complicates the application of die-bonding resin on the reverse sides of wafers, leading to variations in division line width and position, which reduces productivity due to the need for additional steps and potential resin flow into separation grooves.
Innovation Solution
A method involving the formation of separation grooves on the wafer face, application of a protective member, and subsequent resin laying and hardening on the reverse side, allowing for the direct application and separation of die-bonding resin without additional laser processing, thereby maintaining productivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the wafer is divided into individual device chips by grinding the reverse side after applying DAF, then the bonding material is divided into pieces corresponding to individual device chips, but if dicing before grinding is employed, it becomes difficult to rely on the above laying method because the wafer is divided into individual device chips at the same time that the grinding of the reverse side of the wafer is completed
Solution Approach 1:
The patent applies the die-bonding resin on the reverse side of the wafer before the grinding step that divides the wafer into individual chips. This preliminary action allows the resin to be present on each chip when separation occurs, eliminating the need for subsequent resin application steps on individual chips and simplifying the overall process while maintaining productivity
Solution Approach 2:
Instead of the conventional approach of applying bonding material after chip separation or using complex laser division methods, the patent inverts the sequence by applying the resin on the reverse side before dicing and grinding. This inversion allows the resin to be automatically divided with the chips during the mechanical separation process, reducing process complexity
2Manufacturing precision
If a laser beam is applied to the wafer from the side of the separation grooves to divide the die-bonding resin film into pieces corresponding to the semiconductor device chips, then the resin is divided into pieces, but the entire step will be relatively complex
Solution Approach 1:
The patent extracts the resin division function from the complex laser processing step by applying the resin on the reverse side before mechanical separation. The mechanical dicing and grinding processes themselves perform the division function, eliminating the need for separate laser beam processing and reducing overall process complexity while maintaining division accuracy
Solution Approach 2:
The patent uses the mechanical separation process (dicing blade and grinding wheel) as an intermediary to divide both the wafer and the resin simultaneously. This intermediary approach replaces the need for direct laser processing of the resin, simplifying the process while achieving the desired resin division
3Measurement precision
If the projected division lines after the wafer is divided into the individual semiconductor device chips subsequently to the grinding of the reverse side are used, then the division lines can be identified, but the projected division lines tend to vary in width and position from the projected division lines before the wafer is divided and to lose their linearity under the load imposed from a grinding abrasive
Solution Approach 1:
The patent performs the resin application on the reverse side before the grinding step that causes division line distortion. By acting preliminarily, the resin pattern is established on the intact wafer where division lines are still linear and accurately positioned, avoiding the geometric distortions that occur during grinding
Solution Approach 2:
The patent segments the resin application step from the grinding step in time, applying resin before grinding rather than after. This temporal segmentation allows the resin to be applied when the wafer geometry is still intact and accurate, preventing the resin pattern from being affected by subsequent grinding-induced distortion
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 method enables efficient application and separation of die-bonding resin on individual device chips without additional processing steps, maintaining productivity and ensuring consistent division line accuracy.
Implementation Method 1
a method involving the formation of separation grooves on the wafer face, application of a protective member, and subsequent resin laying and hardening on the reverse side, allowing for the direct application and separation of die-bonding resin without additional laser processing
Data Source
AI summary
A wafer processing method of processing a wafer with a plurality of devices disposed in areas demarcated by projected division lines and formed on a face side thereof includes a protective member placing step of placing a protective member for protecting the face side of the wafer on the face side of the wafer which is divided into individual device chips, a resin laying step of laying a die-bonding resin on the reverse sides of the individual device chips by applying a die-bonding liquid resin on the reverse side of the wafer and hardening the applied die-bonding liquid resin, and a separation step of separating the device chips with the die-bonding liquid resin laid on the reverse sides thereof from the wafer.