Photoemission densities of states of sputtered arsenic films

Abstract

The densities of valence states (DOVS) of sputtered As films have been measured with U.V. (hv = 21·2 and 40·8 eV) and X-ray (hv = 1486·6 eV) photoemission techniques. The DOVS of amorphous films sputtered at room temperature are in agreement with those of Ley, Pollak, Kowalczyk, McFeely and Shirley (1973). However, the DOVS of a film sputtered onto substrates at 220°C exhibits a two peak structure in the s-like portions similar to that reported earlier for crystalline As (Ley et al. 1973), while the p-like portions are similar to those reported for amorphous As. This result might be explained by the existence of an amorphous As structure which has only even membered rings. It is more likely, however, that the films were polycrystalline and it is suggested that the data of Ley et al. (1973) for the crystalline form were distorted by angle-dependent photoionization cross section effects.