ProductsKelvin Measurement Technology
Next-Generation Solutions for Precision Resistance Testing
Kelvin measurement (also known as four wire sensing) is a proven method for accurately measuring low resistance values. By separating current (Force) and voltage (Sense) pathways, this technique eliminates the influence of lead and contact resistance, allowing for highly precise detection of the target resistance (Rs).
To perform Kelvin measurements correctly, probes must make stable contact with both the high (H) and low (L) terminals of the device under test. Seiken’s patented Kelvin probe design (Patent No. 5597108) is specially engineered to handle even ultra-small electrodes such as WL-CSP bumps and QFN packages, ensuring stable contact and precise measurement—even in the tightest spaces.
Key Features & Advantages
01 High-accuracy contact for ultra-small electrodes
Traditional probes (needle-type etc) tip is located in the center of the probe, making reliable contact with ultra-small electrodes difficult. Seiken’s Kelvin probes use a design that shifts the Kelvin probe tips toward the outer edge, which positions the contact points closer together—less than 0.1mm apart—while maintaining probe strength and thickness. This enables stable load and accurate resistance measurements, even on small electrodes.
02 New kelvin probe for fine-pitch applications
As devices continue to shrink, electrode pitch is also becoming tighter, making conventional dual-probe setups increasingly difficult. Our next-generation Kelvin probes address this challenge by significantly reducing the gap between contact points, supporting electrodes with a pitch as small as 0.35mm.
This compact gap also improves resistance to alignment errors. In addition, we offer end-to-end fixture solutions, including custom machining and integration with your measurement equipment.
Conventional probe vs. Kelvin probes: a comparison
- Conventional probes
Tip-to-Tip Distance: From 160μm
Pitch (Center-to-Center): From 0.3mm-
To reduce the contact gap between two probes, traditional designs require thinner pins—resulting in reduced contact force, lower current capacity, and weaker mechanical strength.
- New kelvin probes
Tip-to-Tip Distance: From 100μm
Pitch (Center-to-Center): From 0.35mm-
With a specially shaped tip, our Kelvin probes maintain pin thickness while narrowing the contact gap to just 0.1mm. Compared to conventional thin-pin approaches, this ensures higher load stability, greater allowable current, and stronger durability.
They support pitch sizes starting from 0.35mm, covering mainstream packages like WL-CSP and QFN with ease.
- Please note: Depending on the layout and shape of your electrodes or fixture conditions, the actual probe tip may differ from the image. Do not hesitate to send us a message for customized solutions.
Fixture Manufacturing
Due to the special board processing required, we offer Kelvin probes only as part of complete fixtures (e.g., probe cards, sockets, or probe holders), and not as standalone components (except for maintenance). From design to production, we offer one-stop solutions that integrate seamlessly with your test equipment—significantly reducing calibration and setup time, and helping you achieve both high productivity and high accuracy.
Interested in exploring Kelvin technology further? Contact us for detailed specifications, and custom proposals tailored to your measurement needs.
Application Examples
Explore more
- Semiconductor devices
- WL-CSP bump
- QFN package testing, etc.