Compositional and electrical properties of ECR-CVD silicon oxynitrides

Abstract

Silicon oxynitride layers were deposited by electron cyclotron resonance (ECR) plasma enhanced chemical vapour deposition (PECVD). Oxygen, nitrogen and 5% argon diluted silane were used as precursors. The gas composition in the plasma was varied over a wide range to get compositions from pure SiO 2 to SiO x N y layers with around 20% O content. Large N 2 /O 2 flow ratios are required to get significant N concentrations in the SiO x N y deposited layers. Pure Si 3 N 4 layers could only be obtained when O 2 flow was completely suppressed. The infrared spectra of ECR SiO 2 are very similar to those of thermally grown oxides, but significant differences were found between the ECR and the high-temperature CVD Si 3 N 4 spectra. MOS devices fabricated with these layers show that the interface state density increases from about 10 11 to 10 12 cm −2 eV −1 when the layer composition changes from pure SiO 2 to pure Si 3 N 4 .

Optical and structural properties of SiOxNyHz films deposited by electron cyclotron resonance and their correlation with composition

“…21 For SiO x N y H z films, many authors find a dominant absorption band, with a single maximum located at intermediate frequencies between those of SiO 2 and Si 3 N 4 . 1,[11][12][13]30,45,46 This behavior is characteristic of singlephase homogeneous SiO x N y H z and its bonding structure is well described by the RBM previously explained ͓see Eq. ͑3͔͒.…”

“…[6][7][8] Concerning the growth of silicon oxynitride films ͑in the following SiO x N y H z ), research is mainly focused on those techniques with a low thermal budget, according to the requirements of ultralarge scale integration technology, such as rapid thermal processing 4,9,10 or different Plasma Enhanced Deposition techniques. 1,5,6,[11][12][13][14][15] Among these, the electron cyclotron resonance plasma chemical vapor deposition ͑ECR-PECVD͒ method shows several interesting advantages in addition to the low temperature requirement. It does not require the presence of a cathode, which is specially important in processes using corrosive gases.…”

Microstructural modifications induced by rapid thermal annealing in plasma deposited SiOxNyHz films

“…1,2 One of the most extended techniques for the deposition of silicon oxynitride films ͑in the following SiO x N y H z ) at low temperatures is plasma enhanced chemical vapor deposition ͑PECVD͒, [3][4][5] with the remote PECVD 1,6,7 or electron cyclotron resonance ͑ECR-PECVD͒ [8][9][10][11] variants. While these techniques meet the low thermal budget requirement, the quality of the as-deposited dielectric films is not as good as that of thermally grown SiO 2 films.…”

Improvement of nitrogen retained dose using ammonia as a precursor in nitrogen plasma immersion ion implantation of silicon

“…A broad absorption band from 780 to 1000 cm −1 can be observed in all the samples. The asymmetric band can be deconvoluted into a peak centered at approximately 820 cm −1 corresponding to the asymmetric in-plane Si-N stretching vibration mode 11,12 and another one at around 900-1000 cm −1 attributable to the Si-N-O bending mode. 13,14 Complete deconvolution of the broadband is not easy and remains controversial due to the complexity of oxygen coordination with nitrogen and silicon.…”