Electron Impact Dissocation of Molecules Used in Plasma Etching and Deposition of Semiconductors

Cross sections for electron-impact dissociation of molecules are essential to improved modelling of the plasmas used in microelectronics fabrication. The available data on such cross sections for gases of interest in plasma processing is, however, very fragmentary and, furthermore, measurements of these cross sections for dissociation into neutral fragments is very challenging. While computational approaches to obtaining these data are thus clearly of value, calculations of electron-molecule collision are difficult at the low energies of interest and progress has been quite limited. In this project we have developed innovative scalable implementations of our theory of electron collisions which have made it possible to harness the computational power of the largest parallel computers to obtain electron-collision cross sections needed in modelling plasmas used in semiconductor fabrication. We have successfully exploited these algorithms and parallel computer resources to study such cross sections for gases such as CHF3, C2F6, C3F8, c-C4F8, PH3, AsH3, and BCl3.