FIELD-EMISSION BEHAVIOR OF (NITROGEN INCORPORATED) DIAMOND-LIKE CARBON-FILMS

The field emission behavior of diamond-like carbon (DLC) films prepare d by r.f plasma chemical vapor deposition (r.f.-PACVD) was investigate d. DLC films were coated on p-type boron-doped Si (100) wafers using a benzene glow discharge. Nitrogen incorporated DLC films were also pre pared using mixtures of benzene and nitrogen. In both pure and nitroge n incorporated DLC films, the electron emission was enhanced by electr ical breakdown between the anode and the sample surface. After the bre akdown, the effective work functions were measured in the range from 0 .03 to 0.07 eV. The on-set electric field for emission was dependent o n the breakdown behavior. We observed a minimum on-set electric held o f 7 MV m(-1). The emission current was proportional to the number of d amaged regions caused by the electrical breakdown. Auger electron and micro-Raman spectroscopy showed that the electrical breakdown induces the formation of defective SiC compounds in the damaged region. The im proved emission behavior seems to be attributed to the chemical change of carbon in the damaged region, in addition to the field enhancement at the rough surface.