Preparation and Some Properties of Chemically Vapor‐Deposited Si‐Rich SiO2 and Si3 N 4 Films

Abstract

Films of SiO2 and Si3N4 containing excess Si were prepared by chemical vapor deposition at 700~ by the reaction of gaseous Sill4 and N20 for the Si-rich SiO2 and NH3 for the Si-rieh Si3N4. By adjusting the gas-phase ratio of the reactants it was possible to vary the amount of Si in the films. Transmission electron microscopy studies revealed that the films contain two amorphous phases. One phase is amorphous Si while the other is SiO~ or Si3N4. The Si content of the films was measured by electron microprobe analysis. Ellipsometry measurements on the films were made at several angles of incidence in order to measure the film absorption coefficients which were found to increase with increasing Si content. The d-c conduction characteristic for the Si-rich films was found to be nonohmie. The resistivity at any given field was found to decrease with an increase of the Si content.

Synthesis and Luminescent Properties of Silicon Nanocrystals

“…The emission intensity of this band (red region) increases considerably for the SRO monolayer with 5.2 at.% thermally annealed at 1100°C. It has been reported that SRO films deposited by LPCVD or MBE with medium Si-excess (~2.5-5 at.%) produces an efficient PL emission, however Si-NCs have not been observed [17][18][19][20][21]. In our case, Si-NCs were observed from a Si-excess of 5.2 at.% (x = 1.54), as it was shown in images HRTEM [25].…”

“…It can be observed that the deposition rate for SiO 2 is lower (0.15 Å/s) at 100 W while that Si films (0.12 Å/s) at 50 W, where similar thickness (~16-18 nm) is deposited with a PD Si = 2.47 W/cm 2 for a Si film and PD SiO 2 = 5.09 W/cm 2 for a SiO 2 film. Therefore, to ensure Si-excess similar to the reported by other techniques [17][18][19][20][21], SRO films were deposited considering RF-power densities between 1.97 and 3.94 W/cm 2 applied to the Si-target and a PD SiO 2 constant of 5.09 W/cm 2 . Selected the appropriate power densities, SRO monolayers and SRO/SiO 2 ML were deposited at 100°C and annealed at 1100°C.…”

Influence of the SRO as passivation layer on the microwave attenuation losses of the CPWs fabricated on HR-Si

“…In [6], a study of the dependence of the attenuation loss of a CPW on the bias, and on the thermally grown layer (deposited by Low Pressure Chemical Vapor Deposition, LPCVD), has demonstrated that the attenuation loss is not modified by the forward and reverse bias. On the other hand, there have not been any studies of the effect of grown in two steps (thermal oxidation plus Atmospheric Pressure Chemical Vapor Deposition, APCVD), nor the effect of silicon rich oxide (SRO) [7] deposited by LPCVD as the passivation layer of a HR-Si CPW, on the performance of such devices. Thus, in this paper we investigate the microwave performance of the CPW fabricated on HR-Si and using two different passivation layers: grown by thermal oxidation and APCVD, and silicon rich oxide deposited by LPCVD.…”

Cathodo- and Photo- Luminescence of Silicon Rich Oxide Films Obtained by LPCVD

“…At present, different techniques have been employed to produce SRO films, these include plasma enhanced chemical vapor deposition (PECVD) (Pai et al, 1986), low pressure chemical vapor deposition (LPCVD) (Dong et al, 1978), silicon implantation into thermal oxide (SITO) (Pavesi et al, 2000), reactive sputtering (Hanaizumi et al, 2003) and others. An indicator of the Si content in this material is the parameter R 0 , which is the ratio of the partial pressure of the precursor gases (in this case, N 2 O/SiH 4 ) when it is prepared by gas phase deposition methods like CVD (Chemical Vapor Deposition).…”