Manufacturability and reliability of non-halogenated molding compounds

In an effort to answer the global call for "Green Technology", On Semicondu ctor Philippines Inc., has evaluated and qualified molding encapsulant (gre en molding compounds, GMCs) which do not contain the conventional halogenat ed flame-retardant. In this study, the tested resin formulations which are based on biphenyl, ortho-cresol novolac and/or dicyclopentadienyl epoxies c ontain either magnesium hydroxide or phosphorous as flame-retardant. Thermo gravimetric analysis revealed higher thermal stability of these GMCs as com pared to their halogenated counterparts. Adhesion of some of the GMCs to Ni /Pd/Au-plated leadframes was found to be stronger than adhesion of the halo genated molding compounds. Process parameters for molding of GMCs and non-G MCs into SOIC (small outline integrated chip) and TSSOP (thin shrunk small outline package) were comparable. Test samples passed the normal reliabilit y tests conducted for analog devices. The more stringent oil immersion test at 260 degreesC has qualified the phosphorous-containing biphenyl-based ep oxy resin for TSSOP and the magnesium hydroxide-based GMC for the SOIC. Thi s paper reports the results of the characterization, the evaluation and qua lification study conducted for the different GMCs.