Hybrid Die Bonding Transfer for Clean Batch Die Fixing
Solution Overview
Problem
Conventional die stripping methods are inefficient, as they can only peel off one die at a time, leading to slow transfer speeds, low efficiency, and high costs. Additionally, particles on the second surface of the dies are not properly cleaned, causing bonding yield issues.
Innovation Solution
A hybrid die bonding method that involves dicing a wafer into dies, removing particles from both surfaces, peeling off side and corner portions of the second surface, transferring the dies to a first carrier, and then removing the carrier film, allowing for efficient transfer and cleaning of the dies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional die stripping methods are used to peel off one die at a time, then the die can be transferred to the substrate, but the transfer speed is slow and the efficiency is low
Solution Approach 1:
The patent merges multiple die stripping operations into a single batch process. Multiple dies are peeled off from the carrier film simultaneously and transferred to the substrate in one operation, rather than processing one die at a time. This batch processing approach dramatically improves die transfer efficiency and reduces total processing time.
Solution Approach 2:
The patent performs preliminary cleaning of particles from the first surface of the dies before the stripping process. This preliminary action ensures that the bonding surfaces are clean before the dies are separated and transferred, improving bonding yield while enabling efficient batch processing.
2Reliability
If particles on the second surface of the dies are not cleaned, then the process is simpler, but the bonding yield decreases due to lifting, voids, and poor adhesion
Solution Approach 1:
The patent performs preliminary cleaning of particles from both the first and second surfaces of the dies before the stripping and bonding processes. This preliminary cleaning action prevents particles from causing bonding defects such as lifting, voids, and poor adhesion, thereby ensuring high bonding yield without adding complexity to the subsequent processes.
3Reliability
If the carrier film is not removed after die transfer, then the process is simpler, but the dies cannot be properly bonded to the substrate and stacking is compromised
Solution Approach 1:
The patent performs preliminary cleaning of particles from the second surface of the dies before removing the carrier film. This preliminary cleaning action ensures that when the carrier film is removed and the dies are bonded to the substrate, there are no particles to cause bonding defects. This sequence maintains high bonding yield while enabling efficient batch processing.
Data Source
AI summary
A hybrid die bonding method includes the following steps: dicing a wafer into a plurality of dies arranged on a plurality of target blocks of a carrier film, wherein surfaces of each of the dies have no solder and bump; cleaning particulate from first surfaces of the dies; separating side portions and corner portions of second surfaces of the dies from the target blocks; turning the carrier film and transferring the dies to a first carrier, wherein the first surfaces of the dies contact the first carrier; removing the carrier film from the second surfaces of the dies; cleaning particulate from the second surfaces of the dies; and transferring the dies from the first carrier to a substrate, wherein a surface of the substrate has no solder and bump. As such, the method reduces the adhesive force between the dies and the carrier film.