Vacuum Jig Pressure Control for Reflow Substrate Warpage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The reflow process in semiconductor packaging is challenged by defects such as separation, movement, or overlapping of solder balls due to thermal expansion differences in the substrate, which complicates productivity and reliability, and existing solutions are limited in preventing these defects.
Innovation Solution
An adsorption device with a vacuum jig system that adheres to the substrate using negative pressure, controlling the vacuum state to minimize warpage and stabilize the substrate during the reflow process, thereby preventing defects in the connection bumps.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the substrate is heated during the reflow process to bond solder balls, then the solder balls are attached to the substrate, but thermal expansion differences cause substrate warpage leading to solder ball defects
Solution Approach 1:
The patent applies a negative pressure field to the substrate surface during the reflow process, changing the physical parameter of pressure distribution to counteract thermal expansion effects and maintain substrate flatness throughout the heating process
Solution Approach 2:
The negative pressure field is applied before and during heating to preemptively counteract the thermal expansion forces that would cause warpage, preventing substrate deformation before it occurs rather than correcting it after
2Reliability
If design or equipment is changed to predict and prevent substrate deformation, then solder ball defects may be reduced, but process complexity and burden increase
Solution Approach 1:
The patent uses a pneumatic field (negative pressure) to control substrate flatness during reflow, replacing complex mechanical prediction and compensation mechanisms with a simpler pressure-based control system that actively maintains substrate stability
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
The adsorption device effectively reduces thermal expansion-related defects, enhancing the productivity and reliability of semiconductor packages by maintaining consistent thermal expansion across the substrate, allowing for improved design freedom and reduced equipment burdens.
Implementation Method 1
a substrate adsorption portion that protrudes from the bottom portion, and is configured to adhere to a first surface of a substrate by a negative pressure
Data Source
AI summary
An adsorption device for a reflow process according to an embodiment is coupled to a semiconductor package to form a reflow assembly in a reflow process. The semiconductor package includes a substrate and a semiconductor chip disposed at one surface of the substrate. The adsorption device for the reflow process includes a main body and a pressure control member. The main body includes an inner space portion and includes a bottom portion and a substrate adsorption portion that protrudes from the bottom portion to be adhered to the one surface of the substrate in an outer region of the semiconductor chip by a negative pressure. The pressure control member maintains a pressure of the inner space portion.