HATS™ and HATS²™ Thermal Cycling uses a HATS²™ Tester to perform Thermal Shock/Cycling in accordance with IPC-TM-650 method 2.6.7.2 and other industry Thermal Shock/Cycling test methodologies. The HATS²™ Tester uses High Speed "Air" as the heat transfer (fluid) mechanism to heat and cool the test coupons. This methodology changes the air volume in the test chamber surrounding the coupons several times each second. HATS²™ technology provides the maximum possible transfer rate to move heat through the test coupons using Air as a heat transfer mechanism. This changes the limiting thermal factor from the thermal capacity of the test chamber to the coupon's mass and thermal conductivity. HATS²™ technology allows the test coupons to equalize at temperature extremes in 3-6 minutes rather than the 30 minutes required by Dual Chamber and other technologies, greatly speeding up the testing process.
Test Coupon nets are electrically tested (real time) in the HATS²™ Chamber using an updated 4-wire test measurement sub-system to make accurate and repeatable resistance measurements. This allows the HATS²™ tester to determine barrel cracking or interconnection separation in the via structures. HATS²™ testers can test up to 72 IPC-2221B "D" coupons (2 or 3 test nets) , 36 Traditional HATS™ (4-nets) , HATS²™ Single Via Coupons* (7-nets) or Custom 7-net coupons during Reflow Simulation and Thermal Shock/Cycling to determine barrel cracking or interconnection separation in the via structures.
The HATS²™ Tester most closely replicates the "Air" heat transfer mechanism of the widely accepted Dual Chamber technique that has been in use since the 1950's. Other High Speed Thermal Shock technologies use different heat transfer mechanisms like Oil, Liquid Nitrogen, Sand or Circuit Conduction to transfer heat to the coupons which results in different heat transfer rates to and from the test coupons than would occur in air. This will affect test results of the Test Coupons under test. HATS²™ testers can test up to 252 nets (single via structure and daisy-chains) from a variety of industry accepted and custom test coupon styles using up to 7 test nets each. Accomplishing Thermal Shock of 1000 cycles with a full load of coupons can take weeks if not months using other "high speed" technologies due to their limited test coupon/net capacity when compared to the HATS²™ tester. The HATS²™ tester can accomplish 1000 Thermal Shock cycles of 36 to 72 coupons in about a week. Carefully research the methodologies, their heat transfer mechanisms and their ultimate test net capacity before you decide on which technology is right for you.