Ceramic Wiring Substrate with Metal Sealing Ring for Optical Packages

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing optical semiconductor element packages face challenges in reducing transmission loss by placing surface emitting lasers close to leads due to limitations in lead placement precision and productivity, especially when trying to match characteristic impedances for high-speed signal transfer.

Innovation Solution

The use of a ceramic wiring substrate with a hexagonal shape and a metal sealing ring allows for shorter distances between optical semiconductor elements and their electrodes, reducing gold wire lengths and improving signal transmission efficiency, while also facilitating easier alignment and sealing with a metal cap having a glass window.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If leads are sealed in a circular header with glass in the prior art, then hermetic sealing is achieved, but the leads cannot be placed close to the surface emitting laser, resulting in increased transmission loss

Engineering Contradiction:

Improvetransmission lossVSAvoidlead placement precision

Core Design Contradiction:

Loss of energyVSEase of manufacture

Solution Approach 1:

The invention divides the sealing structure into two separate components: a metal sealing ring for sealing the leads and a metal cap with glass window for hermetic sealing. This segmentation allows the leads to be positioned independently close to the laser while maintaining sealing integrity, thereby reducing transmission loss without compromising manufacturing ease.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The metal sealing ring acts as an intermediary component between the leads and the hermetic sealing structure. It provides a dedicated sealing interface that allows leads to pass through close to the laser while the metal cap with glass window provides the hermetic seal, thus mediating between the conflicting requirements of lead placement and sealing.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Loss of energy

If leads are placed closer to the surface emitting laser to reduce transmission loss, then transmission efficiency improves, but alignment and sealing become more difficult

Engineering Contradiction:

Improvetransmission lossVSAvoidalignment precision

Core Design Contradiction:

Loss of energyVSManufacturing precision

Solution Approach 1:

By segmenting the sealing function into the metal sealing ring and metal cap, the invention allows leads to be positioned close to the laser for reduced transmission loss, while the separate cap provides a standardized interface for alignment and hermetic sealing, thus maintaining manufacturing precision despite closer lead placement.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The metal sealing ring provides a standardized sealing surface that creates an equipotential interface for alignment. This standardized interface ensures that even when leads are placed close to the laser, the alignment and sealing processes remain precise due to the consistent geometric reference provided by the sealing ring structure.

Inventive Principle:

Principle #12Equipotentiality

3Reliability

If a circular header with glass is used for sealing, then hermetic sealing is provided, but the structure is complex and difficult to handle

Engineering Contradiction:

Improvehermetic sealingVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The invention segments the sealing system into a metal sealing ring for lead sealing and a metal cap with glass window for hermetic sealing. This segmentation simplifies the overall structure by separating the sealing functions into distinct, manageable components that are easier to manufacture and assemble while maintaining hermetic reliability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention changes the material parameter from glass-to-metal sealing in a circular header to metal-to-metal sealing with a separate glass window in the cap. This parameter change simplifies the structure by using metal components that are easier to manufacture and assemble, while the glass window in the cap maintains the hermetic sealing function.

Inventive Principle:

Principle #35Parameter changes

4Loss of energy

If gold wire length is reduced to improve signal transmission, then transmission efficiency improves, but component placement becomes more constrained

Engineering Contradiction:

Improvesignal transmission lossVSAvoidcomponent placement flexibility

Core Design Contradiction:

Loss of energyVSAdaptability or versatility

Solution Approach 1:

By segmenting the sealing and support functions into the metal sealing ring and metal cap, the invention creates an open mounting area on the ceramic wiring substrate where optical components can be placed flexibly. This allows gold wires to be kept short for reduced signal transmission loss while maintaining component placement flexibility through the reconfigurable mounting space.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS9106047B2Optical semiconductor element package and optical semiconductor device

Publication Date: 2015.08.11 SHINKO ELECTRIC IND CO LTD

AI summary

An optical semiconductor element package, includes a ceramic wiring substrate portion having a mounting area for mounting an optical semiconductor element in a center part, and including an element electrode for connecting the optical semiconductor element, and an external connection electrode connected to the element electrode, and a metal sealing ring provided on the ceramic wiring substrate portion, and including an opening portion exposing the element electrode and the mounting area, in a center part, and a ring-like protruding portion provided to an outer peripheral part of the opening portion.