Wafer Shielding Sheet Composition for Pre-Dicing EMI Coating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing technologies face challenges in providing a reliable electromagnetic wave shielding solution for semiconductor components that can perform batch coating on semiconductor wafers before dicing, ensuring excellent coating properties and versatility for miniaturized, high-density semiconductor packages.
Innovation Solution
An electromagnetic wave shielding sheet with a shielding film comprising a binder component and conductive filler, having specific elongation and Young's modulus properties, is applied to semiconductor wafers before dicing, forming a shield cover layer that can be thermally bonded and cured to ensure excellent adhesion and shielding effectiveness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a shielding film with high conductive filler content is used to improve electromagnetic wave shielding effectiveness, then shielding performance is improved, but the elongation rate and coating properties deteriorate
Solution Approach 1:
The invention optimizes the conductive filler content to 45-85% by mass and controls the binder component composition (including curable compounds with specific molecular weights and high molecular weight resins) to achieve the desired balance between shielding effectiveness and coating properties. This parameter optimization allows the shielding film to maintain both high shielding performance and good elongation rate for proper coating application.
2Weight of moving object
If the shielding sheet is made thin to achieve lighter and smaller electronic devices, then weight and size are reduced, but adhesion strength and shielding effectiveness deteriorate
Solution Approach 1:
The invention uses a composite material system consisting of conductive filler particles dispersed in a binder component matrix (comprising curable compounds and high molecular weight resins). This composite structure provides both the electromagnetic wave shielding capability through the conductive network and the adhesion strength through the polymer matrix, achieving reliable performance even in thin configurations.
Solution Approach 2:
The invention specifies the Young's modulus of the cured sheet should be 100-1000 MPa at 100°C, which optimizes the mechanical properties for maintaining adhesion strength while allowing thin sheet configurations. The elongation rate control at 100-1500% also ensures proper coating behavior on wafer surfaces.
3Productivity
If batch coating is performed on semiconductor wafers before dicing to improve productivity, then manufacturing efficiency is improved, but coating uniformity and adhesion on diced devices deteriorate
Solution Approach 1:
The invention applies the shielding sheet to the semiconductor wafer before dicing (pre-coating), allowing the coating to be formed on the entire wafer surface including future cut surfaces. The sheet is designed with specific mechanical properties (elongation rate 100-1500%, Young's modulus 100-1000 MPa) that enable it to conform to the wafer surface and maintain coating uniformity even after subsequent dicing operations, ensuring consistent shielding on individual devices.
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 shielding sheet enables batch coating on semiconductor wafers, providing reliable electromagnetic wave shielding for both the wafer surfaces and sides of diced semiconductor devices, enhancing productivity and versatility.
Implementation Method 1
a shielding film that includes a binder component and a conductive filler (F)... providing reliable electromagnetic wave shielding
Implementation Method 2
a Young's modulus at 100° C. of a cured sheet after treating the electromagnetic wave shielding sheet at 180° C. for 2 hours is 100 MPa to 1000 MPa
Implementation Method 3
a peeling rate in an adhesion test after performing a pressure cooker test based on JIS K5600-5-6 on a shield cover layer derived from the electromagnetic wave shielding sheet after thermocompression bonding the electromagnetic wave shielding sheet to an entire main surface of a silicon bare wafer at 120° C. and 5 MPa for 3 minutes
Data Source
AI summary
Provided are a highly reliable electromagnetic wave shielding sheet that is capable of performing batch coating on a wafer before dicing and has excellent coating properties, a shielded wafer formed using the electromagnetic wave shielding sheet, a semiconductor device, and a manufacturing method thereof. An electromagnetic wave shielding sheet 3 for performing batch coating on a semiconductor wafer before dicing includes at least a shielding film 30 including a conductive filler (F) and a binder component, has an elongation rate of 100% to 1500% at 100° C., and has a Young's modulus of 100 MPa to 1000 MPa at 100° C. in a cured sheet after treating the electromagnetic wave shielding sheet 3 at 180° C. for 2 hours.