ELECTRICAL MEASUREMENTS OF IODINE-DOPED AMORPHOUS DIAMOND-LIKE FILMS GROWN ON SILICON SUBSTRATE

By incorporating iodine gas during the films' deposition, amorphous di amondlike carbon (a:DLC) films were doped and a:I-DLC films were obtai ned. Optical measurements showed that iodine affects the optical band gap, decrease it from 1.1 to 0.78 ev. Iodine doping decreased the resi stivity by four orders of magnitude, from 10(8) to 10(4) Omega cm. Iod ine doped film was found to have a larger p doping than a:DLC films. t he I-V characteristics of devices made of doped and undoped films grow n on silicon substrates, were studied, ac measurements of these device s have shown that the p doped a:DLC films behave as semiconductors, an d give a rectification with n-type silicon. (C) 1996 American Institut e of Physics.