Kinetics of Epitaxial Silicon Deposition by a Low Pressure Iodide Process

Abstract

This repor t is p r imar i ly a s tudy of the factors wh ich cont ro l the vapor t ranspor t process of s i l icon in a modi f ied c losed tube low pressure cyclic iodide process. The k inet ics of t ranspor t f rom the source to the subst ra te are examined and are found to agree w i th a di f fusion cont ro l led mechan ism. The mode l is usefu l for es t imat ing the depos i t ion ra te under a var ie ty of condit ions. The process is found capab le of depos i t ing s i l icon on si l icon subst ra tes at re la t ive ly h igh depos i t ion rates. Impur i ty dop ing w i th this process is accompl i shed by in-corporat ing the des i red impur i ty into the source sil icon. Vapor phase t ranspor t-c losed tube processes are of cons iderab le i n te res t for ep i tax ia l depos i t ion of semi-conductor mater ia l s (1-4). Essent ia l ly, the process in-vo lves incorporat ing into a c losed tube the substrate, the source of mater ia l to be deposited, and a car r ie r gas. By heat ing the source and subst ra te to d i f ferent