Advanced Lead-Free Server Hardware Reliability Test Methods: Power Age / Power Cycling and Four Point Bend Test Data Results

Reliability assessment of high complexity, high reliability lead-free Server class hardware continues to mature. OEM firms competing in Server and Storage market segments continue to contribute to the industry thermomechanical reliability database through their efforts to assess longer term reliability performance of their electronic hardware products.

Many firms, including IBM Corporation, continue to evaluate system reliability using a suite of accelerated environment tests to assess thermal fatigue, static / dynamic mechanical performance, and combination thermomechanical behavior. These tests typically include (but may not be limited to) accelerated thermal cycling, high temperature Storage, highly accelerated life testing, pull testing, drop testing, pad cratering assessments, and combination shock / vibration exposures.

This paper examines the results of two additional test methods explored to help identify reliability risk points within electrically functional lead-free hardware assemblies. Power Age / Power Cycling / Mini Cycling and Four Point Bend Testing are discussed, with summary results compiled from multiple lead-free Server class hardware product trials. The goal of this compilation assessment was to determine if these additional tests are indeed valuable, and if they can help to identify potential reliability hazards.

Through continued study, the capability of lead-free electronic card assembly and test is being systematically assessed for the extension of its applicability to high complexity, high reliability Server printed circuit board assemblies.