Closer Tolerance Thermal Management at the Device-Under-Test

Effective thermal management has become mandatory for testing devices with faster switching speed transistors that are increasing in numbers in smaller packages. These devices are dissipating more heat while being held at steady test temperature extremes. In most cases, the heat will exit the device-under-test by conduction through the probes in the contactor. Newer probe technologies incorporate in-probe radiation features to support convection for thermal management along with two-point contact for effective conduction heat removal.

Since these are based on convection and conduction heat removal, it is important that one understands and apply Rɵ (thermal resistance) as it relates to the probes impact on thermal management. We must consider this with Rɵ being equal to L/(κ * A) where L= length, κ=thermal conductivity of probe material, and A=cross-sectional surface area. Rɵ = L/(κ * A) is only one part of a systemic understanding of what is required from today’s high performance contactors. This paper will describe how newer probe technologies are being deployed to improve thermal management at the device-under-test while reducing the need for large test handler thermal offsets.

Version: March 2019
Presented by: Bert Brost
Presented at: TestConX