Wafer-Level Burn-In Probe Head With Pogo Pin Contacts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing probe heads for wafer-level burn-in tests face challenges with high production costs and the brittleness of traditional needle probes, which are difficult to replace and maintain.
Innovation Solution
The use of contact clips resembling pogo pins with retractable contacts and a dielectric spacer for improved structural integrity and assembly, along with a metal frame for stability, replaces traditional needle probes to enhance durability and ease of assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional needle probes are used, then manufacturing precision can be maintained, but the probes are brittle and difficult to replace
Solution Approach 1:
The probe head is divided into modular components: alignment plates, spacing elements, and probe assemblies. Each probe can be independently replaced by removing only the affected probe assembly rather than the entire probe head, significantly easing repair operations while maintaining structural integrity through the modular design.
Solution Approach 2:
The probe structure transitions from brittle needle probes to more robust contact clips with pogo pin mechanisms. This parameter change in material form and mechanical structure improves stoutness and replaceability while maintaining the required precision through controlled elastic deformation of the new probe design.
2Measurement precision
If needle probes are used to achieve low pitch testing, then measurement precision is maintained, but production cost increases
Solution Approach 1:
The probe head design allows individual probes to be replaced as disposable components rather than requiring expensive precision needle probes. The alignment plates and spacing elements provide precise positioning for replacement probes, enabling cost-effective maintenance while maintaining testing precision on low pitch circuits.
Solution Approach 2:
The alignment plates and spacing elements are pre-configured with precise geometries and hole patterns that establish accurate probe positioning before actual testing. This preliminary precision structure enables the use of less expensive probe materials while maintaining the measurement precision required for low pitch integrated circuit testing.
3Reliability
If complex probe structures are used to ensure stability, then reliability improves, but device complexity increases
Solution Approach 1:
Multiple functions are merged into integrated components: the alignment plates simultaneously provide mechanical support, precise positioning, and structural alignment. The spacing elements combine spacing, alignment, and probe housing functions. This merging reduces the number of separate components while maintaining reliable electrical connections through the integrated design.
Solution Approach 2:
The alignment plates and spacing elements serve multiple purposes: structural support, precise alignment, probe positioning, and electrical isolation. This multi-functionality reduces overall device complexity while ensuring reliable electrical connections, as the same components that provide mechanical stability also ensure proper electrical contact alignment and insulation.
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 solution results in a more robust and cost-effective probe head with improved assembly efficiency, stable electrical connections, and enhanced insulation, reducing the need for complex welds and simplifying maintenance.
Implementation Method 1
the probe employs a helical spring housed in the stem, whose elastic action pushes the electrical contact in extracted position
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Probe head (1) for wafer-level burn-in test, comprising: a first and a second alignment plates (2, 5) arranged parallel to each other and provided with a plurality of passage holes; at least one spacing element (3) interposed between the first and the second alignment plates (2, 5) and designated for keeping them in a prefixed spaced apart relationship; a plurality of probes (6) housed between the passage holes of the alignment plates (2, 5); said probes (6) comprising a stem (62), an input contact and an output contact at the opposite ends of said stem, wherein the input contact passes through the second alignment plate (5) to electrically connect to a corresponding testing channel of a probe card (10) and the output contact comes out of the first alignment plate (2) and is designed to contact a termination of a wafer (100) to be tested; said output contact (61) being retractable into the stem (62) in opposition to a counteracting elastic element.