Interference Filter Coating on Encapsulated Photo Detector Packages

Solution Overview

Problem

Current methods for packaging integrated circuits with color sensors, such as attaching glass with a filter profile, result in increased packaging costs, complex process controls, low efficiency, and limited miniaturization due to the need for additional layers and parts.

Innovation Solution

A method involving an epoxy-encapsulated package with a pigment filter, where an interference filter layer is directly coated onto the package using materials like SiO2, TiO2, or Al, to provide enhanced optical filtering properties without the need for additional glass layers, utilizing techniques like Ion Beam Sputter or Physical Vapor Deposition for high-volume manufacturing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If glass with filter profile is attached to the package, then optical filtering properties are improved, but packaging cost increases

Engineering Contradiction:

Improveoptical filtering propertiesVSAvoidpackaging cost

Core Design Contradiction:

Object-affected harmful factorsVSEase of manufacture

Solution Approach 1:

The patent combines the filter profile functionality directly into the encapsulant material itself, merging the structural encapsulation function with the optical filtering function into a single integrated component, thereby eliminating the need for separate glass filter attachments and reducing packaging costs

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent uses composite materials by incorporating filter profile materials into the encapsulant composition, creating a multi-functional material that provides both structural encapsulation and optical filtering properties simultaneously

Inventive Principle:

Principle #40Composite materials

2Object-affected harmful factors

If glass with filter profile is attached to the package, then optical filtering properties are improved, but device complexity increases

Engineering Contradiction:

Improveoptical filtering propertiesVSAvoidprocess control complexity

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The patent merges the filter profile functionality directly into the encapsulant material itself, merging the structural encapsulation function with the optical filtering function into a single integrated component, thereby eliminating the need for separate glass filter attachments and reducing packaging costs

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent extracts the filter profile functionality from separate glass components and integrates it directly into the encapsulant material, simplifying the overall package structure and reducing the number of separate parts and attachment processes required

Inventive Principle:

Principle #2Taking out (Extraction)

3Object-affected harmful factors

If glass with filter profile is attached to the package, then optical filtering properties are improved, but manufacturing efficiency decreases

Engineering Contradiction:

Improveoptical filtering propertiesVSAvoidmanufacturing efficiency

Core Design Contradiction:

Object-affected harmful factorsVSProductivity

Solution Approach 1:

The patent incorporates the filter profile into the encapsulant material during the encapsulation process itself, performing the filtering function preparation in advance rather than requiring a separate post-encapsulation filter attachment step, thereby improving manufacturing efficiency

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent combines the filter profile functionality directly into the encapsulant material itself, merging the structural encapsulation function with the optical filtering function into a single integrated component, thereby eliminating the need for separate glass filter attachments and reducing packaging costs

Inventive Principle:

Principle #5Merging (Combining)

4Object-affected harmful factors

If glass with filter profile is attached to the package, then optical filtering properties are improved, but package size increases

Engineering Contradiction:

Improveoptical filtering propertiesVSAvoidpackage size

Core Design Contradiction:

Object-affected harmful factorsVSVolume of moving object

Solution Approach 1:

The patent combines the filter profile functionality directly into the encapsulant material itself, merging the structural encapsulation function with the optical filtering function into a single integrated component, thereby eliminating the need for separate glass filter attachments and reducing packaging costs

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent uses a thin film encapsulant material that incorporates the filter profile, replacing the thick glass substrate with a much thinner flexible coating that provides the same optical filtering function while minimizing volume increase

Inventive Principle:

Principle #30Flexible shells and thin films

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 approach reduces packaging costs and complexity, improves efficiency, and allows for miniaturization by integrating advanced filter profiles directly onto the encapsulated package, enhancing optical filtering capabilities while maintaining robustness and reliability.

Implementation Method 1

utilizing techniques like Ion Beam Sputter or Physical Vapor Deposition for high-volume manufacturing

Methodology Applied

Scientific EffectPhysical Vapor Deposition: Physical Vapour Deposition

Implementation Method 2

utilizing techniques like Ion Beam Sputter or Physical Vapor Deposition for high-volume manufacturing

Methodology Applied

Scientific EffectIon Beam Sputtering: Sputtering

Data Source

PatentUS7951863B2Coated package with filter profile

Publication Date: 2011.05.31 WISTRON CORP

AI summary

Method for packaging a photo detector integrated circuit (IC) and a pigment filter and resulting package are described. An encapsulated package (e.g., an epoxy-encapsulated package) that includes a first surface is provided. A filter layer is then coated directly onto the first surface. The filter layer provides optical filtering properties (e.g., a predetermined filtering profile) in addition to the filtering provided by the pigment filter.