Flatband voltage shift of amorphous silicon nitride metal-insulator-semiconductor diodes

Abstract

The relation between the flatband voltage shift of amorphous silicon nitride metal‐insulator‐semiconductor (a‐SiN:H MIS) diodes and a‐SiN:H deposition conditions is investigated. Significant hysteresis loops are observed in the capacitance‐voltage (C‐V) characteristics for some MIS diodes. This means that the bias scanning sequence and the a‐SiN:H deposition conditions affect the flatband voltage. The dependence of the flatband voltage on bias stress time is also studied in connection with the deposition conditions. A logarithmic time dependence of the flatband voltage is seen for MIS diodes for which a‐SiN:H was deposited at a high NH3/SiH4 gas ratio. These effects are induced from Si‐dangling bonds which exist in a‐SiN:H films.