Relation of Rate and Duration of Evaporation to Background Pressure for the Deposition of Thin Films in Vacuum

Abstract

Measurements of the electrical resistivity of chromium films (50 to 10 000 Å thick) deposited on Pyrex glass at various evaporation rates and background pressures (achieved with an ``electronic'' ion pump) are reported and plotted against the ratio of the arrival rate of molecules from the background gas to that of the vapor atoms at the substrate surface. These points show a large degree of scatter. But, if one plots the resistivity versus the product, background pressure, and duration of evaporation, which determines the total amount of residual gas arriving at the substrate, the result is a smooth curve which can be used to derive an empirical relationship between the pertinent parameters.