Characterization of Photo-Cvd Silicon Oxide

1987 ◽  
Vol 101 ◽  
Author(s):  
R. Padmanabhan ◽  
B. J. Miller ◽  
N. C. Saha

ABSTRACTA photochemical vapor deposition technique was used to deposit silicon oxide films. A range of film properties was produced through changes in the process conditions. Refractive index, indicative of film composition, varied from 1.5 to 2.0, corresponding to oxygen rich and silicon rich conditions, respectively. Etch rate in buffered HF was a strong function of the refractive index, with higher index of refraction yielding lower rates. Film stress was tensile and the magnitude of the stress was again related to the index of refraction. Other properties that were evaluated included pinhole density and adhesion to Si. All the properties were directly relatable to the basic film composition.X-ray photo electron and Auger electron spectroscopy were used to characterize the composition of these films. The Si 2p photoelectron and the Si KLL Auger electron spectra were broad for higher refractive index films and upon deconvolution indicated the presence of different silicon containing species, the natures of which depended upon the actual index of refraction. For stoichiometric films, the predominant constituent was SiO2 and for non-stoichiometric films, varying amounts of Si2O, SiO, Si2O3 and SiO2 were all present.

Author(s):  
W. E. Lee

An optical waveguide consists of a several-micron wide channel with a slightly different index of refraction than the host substrate; light can be trapped in the channel by total internal reflection.Optical waveguides can be formed from single-crystal LiNbO3 using the proton exhange technique. In this technique, polished specimens are masked with polycrystal1ine chromium in such a way as to leave 3-13 μm wide channels. These are held in benzoic acid at 249°C for 5 minutes allowing protons to exchange for lithium ions within the channels causing an increase in the refractive index of the channel and creating the waveguide. Unfortunately, optical measurements often reveal a loss in waveguiding ability up to several weeks after exchange.


2015 ◽  
Vol 15 (10) ◽  
pp. 8016-8022 ◽  
Author(s):  
Jung-Won No ◽  
Dong-Hyun Kim ◽  
Min-Jae Lee ◽  
Duck-Hyun Kim ◽  
Tae-Hun Kim ◽  
...  

Hydrogel ophthalmic lenses containing fluorine-substituted aniline group, titanium silicon oxide nanoparticles, and silver nanoparticles were copolymerized, and the physical and optical properties of the hydrogel lenses were measured. To produce the hydrophilic ophthalmic lenses, the additives were added to the mixture containing HEMA, NVP, MA, EGDMA, and AIBN. The cast mold method was used for the manufacture of the hydrogel ophthalmic lenses, and the produced lenses were completely soaked in a 0.9% NaCl normal saline solution for 24 hours for hydration. The physical properties of the produced macromolecule showed that the water content was 32.5–37.6%, the refractive index was 1.450–1.464, the UV-B transmittance was 0.5–35.2%, and the contact angle was between 56 and 69°. Also, the addition of aniline, titanium silicon oxide, and silver nanoparticles allowed the ophthalmic lenses to block UV. These results show that the produced macromolecule can be used as hydrophilic lenses for ophthalmologic purposes that can block UV.


2020 ◽  
Vol 12 (4) ◽  
pp. 583-588
Author(s):  
Cheong-Il Ryu ◽  
Sung-Hoon Choa

This paper investigated the potential use of argon (Ar) as an alternative carrier gas to helium (He) during the tetraethyl orthosilicate–silicon dioxide (TEOS–SiO2) process using a plasma-enhanced chemical vapor deposition (PECVD) system. Due to the shortage or depletion of conventional He gas, it is important to find alternative gases. This study investigated the effects of the Ar carrier gas on the vaporization efficiency and properties of SiO2 film in the PECVD TEOS–SiO2 process for different process conditions, such as flow rate and plasma power. Ar showed a much higher vaporization efficiency and faster deposition rate than He due to its higher molecular weight and plasma density, indicating that SiO2 film can be deposited considerably faster with less Ar gas. While changes in the film density and residual film stress were also noted depending on the types of carrier gas and amounts or types of plasma power, these changes were insignificant and within the controllable process range during the PECVD process. Therefore, the use of Ar gas can reduce costs and contribute to improvements in productivity without affecting the quality of SiO2 film.


1989 ◽  
Vol 164 ◽  
Author(s):  
D.H. Bouldin ◽  
C.H. Lam ◽  
K. Rose

AbstractHRTEM measurements of silicon rich oxides (SRO) show silicon microcrystals in an oxide matrix [1]. Simple, reliable characterization of this two phase material has been a problem. Ellipsometric measurement of the refractive index is a convenient method for characterizing SRO films. Film composition can be related to the refractive index by Bruggeman's effective medium approximation. In this paper we demonstrate correlation of film compositions obtained by this technique with those obtained by Auger electron spectroscopy (AES)and Rutherford back scattering (RBS). We further demonstrate regimes of LPCVD growth where simple correlation of film composition with [N2 0]/[SiH4] gas ratios is not reliable.


Author(s):  
Chanisa Kanjanasakul ◽  
Frédéric Grisch ◽  
Sawitree Saengkaew ◽  
Gérard Gréhan

The characterization of the properties of fuel droplets around the critical pressure is an experimental challenge. The aim of this study is to measure the size and the refractive index of droplets in high pressure conditions, close to the ones of the critical point. For this purpose, an experimental facility of injection of quasi-monodispersed droplets at high pressure has been developed. Rainbow refractometry has been used to probe droplets in the pressure range 1–50 bar. For water and ethanol droplets, evolutions of their index of refraction with pressure were obtained. For measurements with a liquid fluid near its critical point, ethane was selected because its critical point is 48.7 bar and 32.2 °C. Refractive index measurements on ethane droplets were carried out in the range of pressure and temperature 40–46 bar and 18–25 °C respectively. These unique results show that the rainbow refractometry diagnosis offers undeniable potentials for studying fuel injection under transcritical thermodynamic conditions.


2013 ◽  
Vol 28 (6) ◽  
pp. 671-676 ◽  
Author(s):  
Yu-Qing ZHANG ◽  
Li-Li ZHAO ◽  
Shi-Long XU ◽  
Chao ZHANG ◽  
Xiao-Ying CHEN ◽  
...  

2003 ◽  
Vol 800 ◽  
Author(s):  
Brady J. Clapsaddle ◽  
Lihua Zhao ◽  
Alex E. Gash ◽  
Joe H. Satcher ◽  
Kenneth J. Shea ◽  
...  

ABSTRACTIn the field of composite energetic materials, properties such as ingredient distribution, particle size, and morphology, affect both sensitivity and performance. Since the reaction kinetics of composite energetic materials are typically controlled by the mass transport rates between reactants, one would anticipate new and potentially exceptional performance from energetic nanocomposites. We have developed a new method of making nanostructured energetic materials, specifically explosives, propellants, and pyrotechnics, using sol-gel chemistry. A novel sol-gel approach has proven successful in preparing metal oxide/silicon oxide nanocomposites in which the metal oxide is the major component. Two of the metal oxides are tungsten trioxide and iron(III) oxide, both of which are of interest in the field of energetic materials. Furthermore, due to the large availability of organically functionalized silanes, the silicon oxide phase can be used as a unique way of introducing organic additives into the bulk metal oxide materials. As a result, the desired organic functionality is well dispersed throughout the composite material on the nanoscale. By introducing a fuel metal into the metal oxide/silicon oxide matrix, energetic materials based on thermite reactions can be fabricated. The resulting nanoscale distribution of all the ingredients displays energetic properties not seen in its microscale counterparts due to the expected increase of mass transport rates between the reactants. The synthesis and characterization of these metal oxide/silicon oxide nanocomposites and their performance as energetic materials will be discussed.


2011 ◽  
Vol 1287 ◽  
Author(s):  
Anupama Mallikarjunan ◽  
Laura M Matz ◽  
Andrew D Johnson ◽  
Raymond N Vrtis ◽  
Manchao Xiao ◽  
...  

ABSTRACTThe electrical and physical quality of gate and passivation dielectrics significantly impacts the device performance of thin film transistors (TFTs). The passivation dielectric also needs to act as a barrier to protect the TFT device. As low temperature TFT processing becomes a requirement for novel applications and plastic substrates, there is a need for materials innovation that enables high quality plasma enhanced chemical vapor deposition (PECVD) gate dielectric deposition. In this context, this paper discusses structure-property relationships and strategies for precursor development in silicon nitride, silicon oxycarbide (SiOC) and silicon oxide films. Experiments with passivation SiOC films demonstrate the benefit of a superior precursor (LkB-500) and standard process optimization to enable lower temperature depositions. For gate SiO2 deposition (that are used with polysilicon TFTs for example), organosilicon precursors containing different types and amounts of Si, C, O and H bonding were experimentally compared to the industry standard TEOS (tetraethoxysilane) at different process conditions and temperatures. Major differences were identified in film quality especially wet etch rate or WER (correlating to film density) and dielectric constant (k) values (correlating to moisture absorption). Gate quality SiO2 films can be deposited by choosing precursors that can minimize residual Si-OH groups and enable higher density stable moisture-free films. For e.g., the optimized precursor AP-LTO® 770 is clearly better than TEOS for low temperature PECVD depositions based on density, WER, k charge density (measured by flatband voltage or Vfb); and leakage and breakdown voltage (Vbd) measurements. The design and development of such novel precursors is a key factor to successfully enable manufacturing of advanced low temperature processed devices.


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