Correlation of surface roughness and surface energy of silicon-based materials with their priming reactivity

In this work, the effect of surface roughness and cleaning procedures on reactivity during priming with hexamethyldisilazane is described for four silicon substrates frequently used in semiconductor technology, namely thermally grown SiO2, argon implanted tetraorthosilicate SiO2, polysilicon, and amorphous silicon. Surface energy and roughness were determined by static contact angle measurements and atomic force microscopy. The surface roughness of the silicon substrates increased in the order: thermally grown SiO2, argon implanted tetraorthosilicate SiO2, polysilicon, and amorphous silicon. It was found not to be substantially affected by standard cleaning procedures. The surface energy of all silicon samples decreased with increasing hexamethyldisilazane vapor exposure at 90 A degrees C, and the extent of the decrease corresponded to the surface roughness. Furthermore, a promoting effect on the silylation reaction by an argon implantation process was determined. A correlation between the surface morphology of different silicon materials and reactivity in the silylation reaction with hexamethyldisilazane could be established.