Organic Polymer Dielectrics in Microelectronic Technologies: Reliability Requirements, Testing, and Qualification

This work reviews the dependence of reliability testing results on material processing and properties for polymeric materials used in high density interconnection technologies. Specific data are presented for Cyclotene™ 3022 resins containing divinylsiloxane bisbenzocyclobutene, (CAS 117732-87-3). Silane coupling agents discussed in this study are 3-aminopropyltriethoxysilane (CAS 01760-24-3)(APTES) and 3-methacryloxypropyl trimethoxysilane (CAS 02530-85-0) (MOP-TMS). The dominant modes of failure identified during thermal shock testing of model test structures were edge delamination and sidewall delamination. The edge delamination, occurring along the boundary of via cuts greater than 15 μm deep, can be prevented by appropriate silane coupling chemistry and controlled curing of the dielectric, to produce stress levels less than 30 MPa. The sidewall delamination was also prevented by the use of low stress cure procedures. The importance of sidewall adhesion levels is demonstrated with 2-D Finite Element Analysis. The results of this work suggest that the fabrication of reliable MCM structures with total Cyclotene™ thickness up to 50 μm is possible with the use of the controlled process techniques.