Electrical characterization of the SiON/Si interface for applications on optical and MOS devices
An investigation of the electrical properties of the SiON/n-Si interface is presented for applications in MOS and/or optical devices. The SiON films were deposited onto n-type Si substrates by CVD using different [O]/[N] ratios. Subsequent metallization led to the creation of metal-oxide-semiconductor (MOS) devices and electrical characterization took place in order to identify their electrical properties. Electrical measurements included current–voltage, capacitance–conductance–voltage (C–G–V) measurements and admittance spectroscopy, allowing the determination of the interface state density, the traps time constant and their distribution. Post-deposition annealing was also used and the annealed samples were subjected to the same investigation. The interface state density was found to lie between 1.74 × 1012 eV−1 cm2 and 1.72 × 1011 eV−1 cm−2 and the post-deposition annealing reduced these values.