W-band Test Socket Assembly with Flexible Leadframe and Elastomeric Spacer

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing test contactor technologies are unable to operate effectively at W-band frequencies due to extreme transmission line impedance mismatches, making it difficult to test semiconductor devices used in advanced applications like RADAR systems in modern automobiles.

Innovation Solution

A socket assembly with a housing containing spring probes, a leadframe assembly featuring impedance-controlled microwave structures and a flexible ground plane, and an elastomeric spacer that supports cantilever members, allowing for reliable contact and signal transmission at W-band frequencies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If existing test contactor technology is used, then the structure is simple and easy to manufacture, but it cannot operate at W-band frequencies due to extreme transmission line impedance mismatches

Engineering Contradiction:
Improveoperational capability at W-band frequenciesVSAvoidstructure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The test contactor is divided into separate functional components: a rigid housing providing structural support, a flexible leadframe assembly containing the microwave structures and ground plane, and an elastomeric spacer providing compliance. This segmentation allows each component to be optimized for its specific function while maintaining overall operational capability at W-band frequencies.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The leadframe assembly incorporates flexible microwave structures and a flexible ground plane that can dynamically adapt to positioning variations. The elastomeric spacer provides elastic compliance, allowing the system to maintain reliable electrical contact despite mechanical tolerances or thermal expansion, ensuring consistent performance at W-band frequencies.

Inventive Principle:
Principle #15Dynamics

2Reliability

If rigid structures are used for signal transmission, then manufacturing precision can be maintained, but impedance discontinuities occur due to lack of compliance

Engineering Contradiction:
Improvesignal transmission reliabilityVSAvoidimpedance control precision
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The leadframe assembly uses flexible microwave structures and a flexible ground plane made from thin, compliant materials. These flexible elements can elastically deform to accommodate manufacturing tolerances and assembly variations, maintaining consistent impedance control and reliable signal transmission at W-band frequencies without requiring extremely tight manufacturing precision.

Inventive Principle:
Principle #30Flexible shells and thin films

Solution Approach 2:

The elastomeric spacer changes its mechanical parameters (elastic modulus, compliance) to provide the appropriate level of flexibility. By selecting materials and designs with specific elastic properties, the system achieves optimal compliance that compensates for manufacturing variations while maintaining impedance control for reliable high-frequency signal transmission.

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

Enables reliable testing of semiconductor devices at W-band frequencies by minimizing impedance discontinuities and providing vertical compliance, ensuring accurate and efficient high-speed signal transmission.

Implementation Method 1

an elastomeric spacer adjacent the leadframe assembly, the elastomeric spacer having one or more holes receiving the spring probes therethrough

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

contacting the device under test with the spring probes and the microwave structures, and contacting the device under test with the cantilever members

Methodology Applied
Scientific EffectElectrical Conduction: Conduction (electrical)

Implementation Method 3

the leadframe assembly having impedance controlled microwave structures

Methodology Applied
Scientific EffectElectromagnetic Wave Propagation: Electromagnetic Induction

Data Source

PatentEP3158345B1Test socket assembly and related methods
Publication Date: 2023.11.15 XCERRA CORP
  • EP3158345B1 patent drawingFigure 1
  • EP3158345B1 patent drawingFigure 2
  • EP3158345B1 patent drawingFigure 3~4

AI summary

A socket assembly including a housing that has one or more spring probes therein. The socket assembly further includes a leadframe assembly that has one or more cantilever members, and the leadframe assembly has microwave structures and a flexible ground plane. The socket assembly further includes an elastomeric spacer adjacent the leadframe assembly, the elastomeric spacer having one or more holes receiving the spring probes therethrough.