Performance properties in thick film silicate dielectric layers using molecular modeling

Molecular modeling was employed to understand various behaviors found in thick film dielectric layers derived from solution-based sol–gel formulation in order to aid their development. For instance, for formulations used as planarizing layers, it was discovered that during certain process steps ionic components could be introduced which greatly influences the extent of shrinkage by up to 50%, a phenomenon not normally seen in traditional spin-on glasses (SOG). Thermodynamic calculations showed that specific ionic contaminants contribute to the cure state of the material, potentially depolymerizing the material and promoting the formation of structures that are more easily deformed. Volumetric analysis and compaction modeling demonstrated that the high extent of shrinkage is expected, depending upon the final molecular structure of the silicate. Calculation of the relative modulus of the different suspected structures also showed that depolymerized structures contribute to the ease of compaction.