Characterization of the surface morphology and electronic properties of microwave enhanced chemical vapor deposited diamond films

The surface morphology, electronic structure and atomic bonding configurati ons of chemical vapor deposition (CVD) diamond films prepared at different stages of the deposition process and subjected to different postdeposition surface treatments have been studied by scanning probe microscopy (SPM), sc anning tunneling spectroscopy (STS), and x-ray photoelectron spectroscopy ( XPS) surface analysis techniques. SPM image observations show that (a) in t he biasing nucleation process, diamond crystallites grow in a three-dimensi onal manner and the nucleation density reaches 10(9)-10(10)/cm(2); (b) both as-deposited and boron ion implanted films exhibit a hillock morphology on (100) crystal faces; (c) atomic flatness can be achieved on crystal faces by hydrogen plasma etching. STS analysis indicates that (i) the films obtai ned after an initial biasing nucleation process show a metallic tunneling b ehavior; (ii) both as-deposited and hydrogen plasma etched CVD diamond film s possess typical p-type semiconductor surface electronic properties; (iii) when the as-deposited diamond films are subjected to boron implantation or argon ion etching, the surface electronic properties change from p-type se miconducting behavior to metallic behavior. XPS analysis confirmed that the surfaces for both as-deposited and hydrogen plasma etched diamond films ha ve a tetrahedral atomic bonding configuration. However, the surfaces of bor on ion implanted and argon ion etched diamond films exhibited an amorphous carbon-like feature which can be attributed to the surface damage caused by ion bombardment. (C) 2000 American Vacuum Society. [S0734-211X(00)18206-X] .