Vertical Probe Head With Dual Spring Constants for Stable Testing

Solution Overview

Problem

Probe heads in existing technologies face challenges in simultaneously meeting the different physical requirements for connecting devices under test and testing instruments, as probes often struggle to accommodate varying connection conditions effectively.

Innovation Solution

A probe head design with an upper and lower section having distinct spring constants, where the upper section has a first spring constant and the lower section has a second, different spring constant, allowing for tailored connections to specific devices or components, with the lower section being fixed to prevent movement along the penetrating direction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a probe structure body with uniform spring constant is used, then the structure is simple and easy to manufacture, but it cannot simultaneously satisfy different physical requirements for connecting devices under test and testing instruments

Engineering Contradiction:

Improveadaptability to different connection conditionsVSAvoidprobe structure complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The probe structure body is divided into multiple sections along its length, with each section having a different spring constant. This segmentation allows the probe to provide different mechanical characteristics for different connection requirements - a softer upper section for connecting to testing instruments and a stiffer lower section for connecting to devices under test, thereby resolving the contradiction between adaptability and structural simplicity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the probe structure body are designed with locally optimized spring constants tailored to specific connection needs. The upper section has a first spring constant optimized for instrument connections, while the lower section has a second spring constant optimized for device connections. This local quality differentiation enables the single probe structure to satisfy multiple different physical requirements simultaneously.

Inventive Principle:

Principle #3Local quality

2Adaptability or versatility

If the probe structure body is made flexible to accommodate different connection conditions, then adaptability improves, but stability and reliability of connection deteriorate

Engineering Contradiction:

Improveflexibility in connectionVSAvoidconnection stability

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The probe structure body is divided into multiple sections along its length, with each section having a different spring constant. This segmentation allows the probe to provide different mechanical characteristics for different connection requirements - a softer upper section for connecting to testing instruments and a stiffer lower section for connecting to devices under test, thereby resolving the contradiction between adaptability and structural simplicity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different sections of the probe structure body are designed with locally optimized spring constants tailored to specific connection needs. The upper section has a first spring constant optimized for instrument connections, while the lower section has a second spring constant optimized for device connections. This local quality differentiation enables the single probe structure to satisfy multiple different physical requirements simultaneously.

Inventive Principle:

Principle #3Local quality

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 design enhances operational convenience, stability, and reliability by ensuring that the connection of one end portion does not affect the state of the other, thereby improving flexibility and reliability in electrical testing.

Implementation Method 1

An upper section of the probe structure body closer to the upper guide plate relative to the fixed portion has a first spring constant, and a lower section of the probe structure body farther from the upper guide plate relative to the fixed portion has a second spring constant different from the first spring constant

Methodology Applied

Scientific EffectSpring constant: Elasticity

Data Source

PatentUS12474374B2Probe head and vertical probe card comprising the same

Publication Date: 2025.11.18 SILICON FUTURE MFG CO LTD

AI summary

The present invention provides a probe head, comprising: an upper guide plate with a first through hole; a lower guide plate with a second through hole; and a probe structure body with a first end portion, a second end portion and a needle body. The upper guide plate and the lower guide plate jointly define an inner accommodation space. The first end portion is disposed in the first through hole, and the second end portion is disposed in the second through hole. The needle body is located between the first end portion and the second end portion, and is accommodated in the inner accommodation space. The second end portion has a fixed portion positioned on the lower guide plate, and the fixed portion has no degree of freedom to move along the penetrating direction of the second through hole. The upper section of the probe structure body relative to the fixed portion has a first spring constant, and the lower section of the probe structure body relative to the fixed portion has a second spring constant. The present invention also provides a vertical probe card including the above-mentioned probe head.