The modification of silicon surfaces is presently of great interest to the semiconductor device community. Three distinct areas are the subject of inquiry: first, modification of the silicon electronic structure; second, passivation of the silicon surface; and third, functionalization of the silicon surface. It is believed that surface modification of these types will vii *.. Vlll has been at my side throughout my graduate career and my son, Casey Jeffrey, has really livened up the end. My parents, in-laws, and grandparents have provided support when the going got tough. I appreciate the help that was provided by my brothers and sister. I was greatly helped by the friendship of Ed Hanson and Matt Linford.