Conditions for the Creation of Dislocations by Diffusion of Phosphorus into Silicon

Abstract

Introduction Phosphorus diffusion into silicon has been widely studied in the past because of its great importance for fabrication of silicon devices. It has been well established that high-temperature diffusion of large concentrations of phosphorus into shallow surface layers of silicon results in lattice strain which is often relieved through the creation of dislocations /1 to 4/. Also, it has been established that dislocations created by phosphorus diffusion into silicon usually a r e arranged in regular patterns along common slip planes /4/. Principally, the strain and dislocations a r e believed to result from the mismatch between the ionic radius of the phosphorus atom that occupies a substitutional site and the covalent radius of the silicon /l/.