EMI Shielding Layer Formation on BGA Packages Using Base Tape

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing methods for forming electromagnetic interference (EMI) shielding layers on ball grid array (BGA) semiconductor packages are costly due to the need for expensive equipment and complex processes, including the use of releasing agents, which increase operational complexity and costs.

Innovation Solution

A method involving a base tape with an elastic adhesive attaching portion is used to form a package-tape assembly, where the BGA semiconductor package is pressed against the tape to sink solder balls into the attaching portion, and a conductive layer is sputtered onto the assembly to create an EMI shielding layer, excluding the lower surface, and then the tape is removed, thereby simplifying the process and reducing costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a tray with liquid adhesive and releasing agent is used to form EMI shielding layer, then the shielding layer can be formed on the semiconductor package, but the equipment cost and manufacturing cost become very high

Engineering Contradiction:

ImproveEMI shielding layer formationVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent uses a disposable base tape with adhesive layer instead of expensive reusable trays and releasing agents. The base tape is discarded after single use, eliminating the need for costly equipment and complex releasing agent application processes while maintaining effective EMI shielding layer formation.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent extracts and eliminates the expensive tray and releasing agent components from the manufacturing process. By using only the essential base tape with adhesive, the method removes unnecessary equipment and materials that contribute to high manufacturing costs while preserving the core functionality of EMI shielding layer formation.

Inventive Principle:

Principle #2Taking out (Extraction)

2Reliability

If a tray with releasing agent is used to form EMI shielding layer, then the shielding layer can be formed, but the process becomes complicated

Engineering Contradiction:

ImproveEMI shielding layer formationVSAvoidprocess complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent removes the releasing agent step and tray components from the process, leaving only the essential base tape application. This extraction of unnecessary process steps dramatically simplifies the manufacturing procedure while maintaining effective EMI shielding layer formation on the semiconductor package.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent combines the adhesive function and the support function into a single base tape component. The base tape integrates the adhesive layer that both holds the semiconductor package during sputtering and serves as a disposable substrate, eliminating the need for separate tray and releasing agent applications.

Inventive Principle:

Principle #5Merging (Combining)

3Productivity

If solder balls are not prevented from electrical connection during sputtering, then the package can be processed, but short circuits may occur between solder balls

Engineering Contradiction:

Improveprocessing efficiencyVSAvoidelectrical connection reliability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The adhesive layer on the base tape acts as an intermediary insulating material between the solder balls. During sputtering, the adhesive prevents electrical contact between adjacent solder balls while allowing the EMI shielding layer to be deposited, thus avoiding short circuits without affecting processing efficiency.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 effectively forms an EMI shielding layer on BGA semiconductor packages quickly and cost-effectively, improving productivity and reducing manufacturing expenses by using a base tape to simplify the process and prevent electrical connections between solder balls.

Implementation Method 1

a base tape having an attaching portion that is thicker than a height of the solder balls and is formed of an elastic adhesive material

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 2

forming the EMI shielding layer on the BGA semiconductor package by sputtering a conductive layer on the package-tape assembly

Methodology Applied

Scientific EffectSputtering: Sputtering

Data Source

PatentUS9613913B2Method of forming electromagnetic interference shielding layer of ball grid array semiconductor package and base tape for the method

Publication Date: 2017.04.04 PROTEC CO LTD

AI summary

Provided are a method of forming an electromagnetic interference (EMI) shielding layer of a ball grid array (BGA) semiconductor package, and a base tape used in the method, and more particularly, a method of forming a shielding layer for blocking EMI, on an upper surface and lateral surfaces of a BGA semiconductor package having a lower surface, on which a plurality of solder balls are formed, and a base tape used in the method.According to the method of forming an EMI shielding layer of a BGA semiconductor package, the EMI shielding layer may be formed on the BGA semiconductor package quickly, easily, and effectively by using the base tape, thereby not only improving process productivity but also remarkably reducing the manufacturing costs.