PROCESSING CONCERNS FOR MULTI-LEVEL THIN FILM METALLIZATION.

Evaporation of multi-layer metallic thin film structures, bearing reactive metals like Ti, requires good control over the metallization process. During sequential deposition, the delay between the deposition of Ti and the next layer (X) and the pressure in the evaporation chamber during metallization, determine the impurity contents at the Ti/X interface which in turn influences the electrical and mechanical properties of the structure. The mechanical strength of the structure is, however, more sensitive to contamination at the Ti/X interface. The use of multiple electron gun systems to eliminate delay during deposition and the practice of pre-evaporating Ti, to clean the chamber prior to evaporating the thin film structure, will ensure electrically and mechanically sound structures.