High-temperature lead-free solders with effects

Other component reliability issues related to lead-free solders include flip chips and wafer level CSPs with lead-free solder bumps and balls, where the higher soldering temperature and higher stiffness of the lead-free solder can adversely effect the reliability of the low-k dielectric layer on the die. Low k dielectric is needed for high speed applications, but is typically more fragile and prone to cracking. 

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