Polymer surface treatment to reduce RDL leakage and solve delamination issue: YE: Yield enhancement/learning

IC backend chip scale package Re-Distribution Layer (RDL) routing space is getting smaller and pattern density is getting higher while device technology has been scaling down continuously. However, smaller routing space will induce higher leakage current due to higher occurrence of metal residue remaining. Higher metal density will also induce poor 2 polymer films adhesion and cause higher failure rate of component level reliability test in high temperature and humidity (u-HAST). Hereunder, a new enhanced-plasma methodology was developed to replace the ordinary single plasma to reduce RDL leakage current and improve 2 polymer films adhesion to have a more robust reliability performance by avoiding moisture permeating into 2polymer films interface in high humidity and temperature circumstance.