EFFECT OF HYDROGEN ON THE PROPERTIES OF POLYCRYSTALLINE DIAMOND THIN-FILMS

Microwave plasma-assisted chemical vapor deposition has been used to g row undoped and doped diamond on molybdenum and silicon substrates. Cu rrent-voltage (I-V), characteristics, secondary electron emission and depth profiles for various elements by secondary ion mass spectrometry of diamond films have been measured before and after annealing in nit rogen gas at 425-degrees-C. We have analyzed the films for morphology and chemical nature by scanning electron microscopy and Raman spectros copy respectively. Hydrogen present in the as-deposited diamond films resulted in a decrease in the electrical resistivity and an increase i n secondary electron yield. Furthermore, we have observed an increase in resistivity and decrease in yield on annealing. Comparison of these results is presented in this paper.