Mixed Mold Compound for Electronic Circuit Encapsulation

Solution Overview

Problem

Conventional methods for encapsulating electronic components with ferromagnetic materials, such as pick and place and electroplating, are time-consuming and increase production costs, limiting the efficiency and effectiveness of energy storage and signal transmission in inductors and conductors.

Innovation Solution

Incorporating ground or atomized ferromagnetic materials into a conventional mold compound to create a mixed mold compound with increased permeability, which is then used to encapsulate electronic components through a transfer molding process, allowing for efficient dispersion of ferromagnetic particles around conductors and wire bonds, thereby enhancing inductance and signal transmission properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If ferromagnetic materials are placed proximate electronic components by pick and place or electroplating, then inductance and energy storage are improved, but production time and cost increase

Engineering Contradiction:

ImproveinductanceVSAvoidproduction time

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent combines the ferromagnetic material placement function with the mold compound encapsulation process. The ferromagnetic particles are mixed into the mold compound material, so that a single encapsulation operation simultaneously provides both mechanical protection and magnetic field enhancement, eliminating the need for separate pick-and-place or electroplating steps

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent creates a composite mold compound material by mixing ferromagnetic particles (such as ferrite, iron powder, or nickel) with the base mold compound material. This composite material provides both the structural/protective functions of the mold compound and the magnetic field enhancement properties of the ferromagnetic particles

Inventive Principle:

Principle #40Composite materials

2Reliability

If ferromagnetic materials are placed proximate electronic components by pick and place or electroplating, then inductance and energy storage are improved, but production cost increases

Engineering Contradiction:

ImproveinductanceVSAvoidproduction cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent combines the ferromagnetic material placement function with the mold compound encapsulation process. The ferromagnetic particles are mixed into the mold compound material, so that a single encapsulation operation simultaneously provides both mechanical protection and magnetic field enhancement, eliminating the need for separate pick-and-place or electroplating steps

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent changes the physical form of ferromagnetic materials from bulk pieces or platings to fine particles that can be uniformly distributed within the mold compound. This particle form factor enables automated mixing and encapsulation processes, reducing labor costs and improving manufacturing efficiency

Inventive Principle:

Principle #35Parameter changes

3Ease of manufacture

If conventional mold compound is used for encapsulation, then manufacturing is simple, but permeability and signal transmission are insufficient

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidpermeability

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent creates a composite mold compound material by mixing ferromagnetic particles (such as ferrite, iron powder, or nickel) with the base mold compound material. This composite material provides both the structural/protective functions of the mold compound and the magnetic field enhancement properties of the ferromagnetic particles

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent changes the physical form of ferromagnetic materials from bulk pieces or platings to fine particles that can be uniformly distributed within the mold compound. This particle form factor enables automated mixing and encapsulation processes, reducing labor costs and improving manufacturing efficiency

Inventive Principle:

Principle #35Parameter changes

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 method significantly increases the relative permeability of the mold compound, leading to enhanced inductance and signal transmission capabilities of electronic components, reducing production time and costs by eliminating labor-intensive placement processes and ensuring consistent ferromagnetic material distribution around components.

Implementation Method 1

Ferromagnetic materials include, the following materials, which are listed with their maximum relative permeability in parenthesis: ferrite M33 (750); nickel (600); ferrite N41 (3000); iron (5000); ferrite T38 (10,000); silicon GO steel (40,000); and supermalloy (1,000,000).

Methodology Applied

Scientific EffectFerromagnetism: Ferromagnetism

Data Source

PatentUS9378882B2Method of fabricating an electronic circuit

Publication Date: 2016.06.28 TEXAS INSTRUMENTS INC

AI summary

Circuits and methods of fabricating circuits are disclosed herein. A method of fabricating an electronic circuit includes placing an electronic component on a substrate. A ferromagnetic material is mixed into a mold compound to produce a mixed mold compound having an increased permeability over the mold compound. The mixed mold compound is applied to the substrate by way of a transfer mold process, wherein the mixed mold compound encapsulates the electronic component.