Electrical properties of plasma polymerized thin films deposited athigh substrate temperature

摘要

The authors successfully prepared thin dielectric films containingsilicon nitride-type linkages by plasma polymerization oftetramethylsilane in the presence of ammonia. The content of siliconnitride-type inorganic linkage in the polymer film increased with anincrease in the substrate temperature from 25° C to 200° C. Therate of deposition of film decreased with an increase in substratetemperature. The dielectric constant and dissipation factor decreasedwith an increase in frequency. The loss tangent and dielectric constantdecreased with an increase in the film deposition temperature from25° C to 200° C at all the frequencies with an exception at thehighest frequency. This has been attributed to the higher siliconnitride content in the films deposited at higher temperatures. A gradualincrease in dielectric constant and loss tangent was observed for thefilms with an increase in measurement temperature. Aging of the plasmadeposited films, both in air and oil, improved the dielectricproperties. The DC resistivity increased with an increase in filmdeposition temperature. From these results it is concluded that, ingeneral, the dielectric properties of plasma polymerized films can beimproved by increasing the deposition temperature from ambient (which iscommonly used) to 200° C