STRUCTURAL AND ELECTRICAL-PROPERTIES OF SINX-H FILMS

The electronic structure in off-stoichiometric SiN(x):H films has been investigated using ted in plasma-deposited films prepared from a mixt ure of ammonia (NH3) and silane (SiH4) for various gas ratio R (=NH3/S iH4). Metal-insulator-metal diodes incorporating SiN(x):H films prepar ed using R values from 0.2 to 5 were fabricated and the electrical cha racteristics of these diodes were measured. The properties of the SiN( x):H films were also evaluated by ultraviolet-visible, infrared, and x -ray photoelectron spectroscopy. For the R range investigated, the opt ical band gaps and x values in the films varied from 1.6 to 3.6 eV and from 0.19 to 1.09, respectively. The hydrogen bonding configuration a lso changed from isolated Si-H bonds, with no adjacent Si-N bond, to m ulti-N-bonded Si-H bonds as R was increased. The anomalous behavior of the dynamic relative permittivity was observed and the existence of t wo traps with a different energy was deduced. The results of these ele ctrical measurements are discussed and related to those of the composi tional investigations.