Structure of sputtered silicon suboxide single- and multi-layers

The microscopic structure of silicon-rich and oxygen-rich SiOx (0sputter deposition of Si in an Ar–O2 mixture. By using stacks of very thin layers, we have fabricated spatially inhomogenous structures as a model for the RMM. All stacks have the same total thickness (256 nm) and the thickness/layer is from 128 nm down to 2 nm. The composition and spatial inhomogeneities in the stacks were investigated by ion beam analyses techniques (Rutherford backscattering spectrometry (RBS) and high resolution RBS) and electron paramagnetic resonance (EPR). Infrared spectroscopy (IR) was used to study the local atomic structure of the samples. The EPR measurements, using different values of the microwave power, revealed two types of uncharged dangling bond defects. Their density amounts to approximately 1020 cm−3. We are able to detect spatial inhomogeneities down to 2 nm. This value is a firm upper limit for the spatial extension of domains in an RMM material.