Fabrication of planar SiON optical waveguide and its characterization

2005 ◽  
Vol 891 ◽  
Author(s):  
Yu-Jeong Cho ◽  
Yeong-Cheol Kim
Keyword(s):  
Refractive Index ◽  
Gas Flow ◽  
Chemical Vapor ◽  
Core Layer ◽  
Silicon Oxynitride ◽  
Flow Ratio ◽  
Cladding Layer ◽  
Gas Flow Ratio ◽  
Index Contrast ◽  
Optical Planar Waveguide

ABSTRACTSilicon oxynitride (SiON) was deposited as a core layer on a silica (SiO2) under-cladding layer by using plasma enhanced chemical vapor deposition (PECVD). The refractive index of the SiON core layer was varied between 1.45 and 1.78 by changing the gas flow ratio of SiH4, N2O and NH3. Etching experiments were performed using a dry etching equipment to fabricate the SiON core. An optical planar waveguide with a core and under-cladding thicknesses of 6 μm and 8 μm, respectively, and a refractive index contrast (Δn) of 7 % has been fabricated.

Effect of film chemistry on refractive index of plasma-enhanced chemical vapor deposited silicon oxynitride films: A correlative study

2008 ◽  
Vol 23 (5) ◽  
pp. 1433-1442 ◽  
Author(s):  
S. Naskar ◽  
S.D. Wolter ◽  
C.A. Bower ◽  
B.R. Stoner ◽  
J.T. Glass
Keyword(s):  
Refractive Index ◽  
Hydrogen Concentration ◽  
Photoelectron Spectroscopy ◽  
Gas Flow ◽  
Chemical Vapor ◽  
Silicon Oxynitride ◽  
Rf Plasma ◽  
Flow Ratio ◽  
Plasma Chemical Vapor Deposition ◽  
Gas Flow Ratio

Thick SiOxNy films were deposited by radiofrequency (rf) plasma chemical vapor deposition using silane (SiH4) and nitrous oxide (N2O) source gases. The influence of deposition conditions of gas flow ratio, rf plasma mixed-frequency ratio (100 kHz, 13.56 MHz), and rf power on the refractive index were examined. It was observed that the refractive index of the SiOxNy films increased with N and Si concentration as measured via x-ray photoelectron spectroscopy. Interestingly, a variation of refractive index with N2O:SiH4 flow ratio for the two drive frequencies was observed, suggesting that oxynitride bonding plays an important role in determining the optical properties. The two drive frequencies also led to differences in hydrogen concentration that were found to be correlated with refractive index. Hydrogen concentration has been linked to significant optical absorption losses above index values of ∼1.6, which we identified as a saturation level in our films.

The Effects of Deposition Parameters on the Properties of SiO2 Films Deposited by Microwave Ecr Plasmas

1993 ◽  
Vol 334 ◽  
Author(s):  
T. T. Chau ◽  
P. M. Lam ◽  
K. C. Kao
Keyword(s):  
Refractive Index ◽  
Deposition Rate ◽  
Gas Flow ◽  
High Pressures ◽  
Thermally Grown Oxide ◽  
Film Deposition ◽  
Flow Ratio ◽  
Gas Flow Ratio ◽  
Film Deposition Rate ◽  
Thermally Grown

AbstractElectronic and physical properties of SiO2 films deposited by microwave ECR plasmas of the mixtures of SiH4 and N2O have been measured as functions of the pressure and the gas-flow ratio of N2O to SiH4 gases in the processing chamber. Experimental results show that the film deposition rate increases with increasing SiH4 concentration, that is, with decreasing gas-flow ratio. The films deposited at N2O/SiH4 gas-flow ratios smaller than 10 tend to have a refractive index higher than the thermally grown oxide. However, for the N2O/SiH4 gas-flow ratios between 10 and 20, the films have the refractive index close to that of thermally grown oxide, which is about 1.45-1.46. The film deposition rate increases linearly with increasing pressure. In general, the films deposited at high pressures (>100 mTorr) have a higher refractive index as compared with the thermally grown oxide; also films deposited at high pressures have more electron traps. Good quality SiO2 films can be deposited at pressures with the range of 20 -50 mTorr and the N2O/SiH4 gas-flow ratio of 10.

Synthesis and Characterization of Siof Thin Films Deposited by Ecrcvd for Ulsi Multilevel Interconnections

1996 ◽  
Vol 427 ◽  
Author(s):  
Seoghyeong Lee ◽  
Jong-Wan Park
Keyword(s):  
Dielectric Constant ◽  
Refractive Index ◽  
Photoelectron Spectroscopy ◽  
Gas Flow ◽  
Fluorine Content ◽  
Fluorine Concentration ◽  
Flow Ratio ◽  
Ecr Plasma ◽  
Gas Flow Ratio

AbstractLow dielectric constant fluorine doped silicon oxide films were deposited by using ECR plasma CVD with SiF4 and O2 as source gases diluted in Ar gas. Characterization of films was carried out in terms of various gas flow ratios (SiF4/O2 = 0.2 ∼ 1.6). The microwave power and substrate temperature during deposition were fixed at 700W and 300°C, respectively. The chemical bonding structure of the films was evaluated by Fourier transform infrared spectroscopy (FTIR), fluorine concentration by X-ray photoelectron spectroscopy (XPS) and refractive index by ellipsometry. Dielectric constant was determined from C-V measurements at 1MHz. FTIR spectra shows that as the fluorine concentration increases, peak intensities of Si-F bonding and shoulder peak at around 1160cm−1 of Si-O stretching mode increased. Moreover, with increasing the fluorine concentration in the SiOF film, the peak position of Si-O stretching mode shifts to the higher wavenumber side. The Si-F2 bond peak is observed to rise when the SiF4/O2 gas flow ratio is larger than 1.0. Refractive index and film density decreased with increasing the SiF4/O2 gas flow ratio. The SiOF film deposited at SiF4/O2 gas flow ratio of 1.0 exhibited fluorine content of 11.8 at.% and dielectric constant of 3.14.

scholarly journals Optimization of Fabrication Process for SiON/SiOx Films Applicable as Optical Waveguides

Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 574
Author(s):  
Ľuboš Podlucký ◽  
Andrej Vincze ◽  
Soňa Kováčová ◽  
Juraj Chlpík ◽  
Jaroslav Kováč ◽  
...  
Keyword(s):  
Refractive Index ◽  
Flow Rate ◽  
Optical Waveguides ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Vapor ◽  
Silicon Oxynitride ◽  
Force Microscopy ◽  
Atomic Force ◽  
Index Contrast ◽  
The Impact

In this paper, the analysis of silicon oxynitride (SiON) films, deposited utilizing the plasma enhanced chemical vapor deposition (PECVD) process, for optical waveguides on silicon wafers is presented. The impact of N2O flow rate on various SiON film properties was investigated. The thickness and refractive index were measured by micro-spot spectroscopic reflectometry and confirmed by spectroscopic ellipsometry. The chemical composition of SiON films was analyzed using Secondary Ion Mass Spectrometry (SIMS). The surface roughness was analyzed using Atomic Force Microscopy (AFM). Increasing the N2O flow rate during deposition caused the deposition rate to increase and the refractive index to decrease. By changing the flow rate of gases into the chamber during the PECVD process, it is possible to precisely adjust the oxygen (O2) ratio and nitrogen (N2) ratio in the SiON film and thus control its optical properties. This was possibility utilized to fabricate SiON films suitable to serve as a waveguide core for optical waveguides with a low refractive index contrast.

Field emission characteristics of carbon nanotubes synthesized by C3H4 and NH3 gases

2002 ◽  
Vol 727 ◽  
Author(s):  
Taewon Jeong ◽  
Jae Hee Han ◽  
Whikun Yi ◽  
SeGi Yu ◽  
Jeonghee Lee ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Field Emission ◽  
Gas Flow ◽  
Field Enhancement ◽  
Chemical Vapor ◽  
Emission Characteristics ◽  
Flow Ratio ◽  
Multiwalled Carbon ◽  
Turn On ◽  
Gas Flow Ratio

AbstractUsing a gas mixture of propyne (C3H4) and ammonia (NH3) as a carbon precursor, we have successfully synthesized multiwalled carbon nanotubes (CNTs) by the direct current (dc) plasma enhanced chemical vapor deposition (PECVD) onto Co-sputtered glass at 550°C. As the flow ratio of NH3 to C3H4 in the mixture gas increased, the crystallinity and alignment of CNTs were improved. In addition, the field emission characteristics of CNTs were also improved. the turn-on voltage became lower, and the current density and the field enhancement factor were more increasing. Raman spectroscopy and scanning electron microscopy were utilized to confirm the effect of the gas flow ratio on CNTs. Therefore, the gas flow ratio was found to be one of important factors to govern the crystalline and field emission characteristics of CNTs. The growth mechanism of CNTs using a C3H4 gas is under investigation with the possibility that three carbon atoms in a C3H4 molecule is converted directly to a hexagon of a CNT by combining two molecules.

Plasma Etching of SiO2 with CF3I Gas in Plasma-Enhanced Chemical Vapor Deposition Chamber for In-Situ Cleaning

2019 ◽  
Vol 11 (12) ◽  
pp. 1667-1672
Author(s):  
Jin-Seong Park ◽  
In-Sung Park ◽  
Seon Yong Kim ◽  
Taehoon Lee ◽  
Jinho Ahn ◽  
...  
Keyword(s):  
Plasma Etching ◽  
Vapor Deposition ◽  
Etch Rate ◽  
Gas Flow ◽  
Chemical Vapor ◽  
Chamber Pressure ◽  
Flow Ratio ◽  
Deposition Chamber ◽  
Gas Flow Ratio ◽  
Chamber Temperature

Non-global-warming CF3I gas has been investigated as a removal etchant for SiO2 film. Thermally fabricated SiO2 films were etched by the plasma generated with a gas mixture of CF3I and O2 (CF3I/O2) in the plasma-enhanced chemical vapor deposition chamber. The etch rate of SiO2 films was studied along with the process parameters of plasma etching such as chamber pressure, etching gas flow ratio of CF3I to CF3I/O2, plasma power, and chamber temperature. Increasing the chamber pressure from 400 to 1,000 mTorr decreased the etch rate of SiO2 film. The etch rate of this film showed a minimum value at a gas flow ratio of 0.71 in CF3I to CF3I/O2 and then increased at a higher CF3I gas flow ratio. In addition, the elevated plasma power increased the etch rate. However, the chamber temperature has little effect on the etch rate of SiO2 films. When only CF3I gas without O2 was supplied for etching, polymerized fluorocarbon was formed on the surface, indicating the role of oxygen in ashing the polymerized fluorocarbon during the etching process.

Control and Variation of Stress in Pecvd SiNx Films on InP

1988 ◽  
Vol 130 ◽  
Author(s):  
J. Lopata ◽  
W. C. Dautremont-Smith ◽  
J. W. Lee
Keyword(s):  
Compressive Stress ◽  
High Frequency ◽  
Gas Flow ◽  
Plasma Reactor ◽  
Low Frequency ◽  
Chemical Vapor ◽  
Flow Ratio ◽  
Deposition Parameters ◽  
Chemical Vapor Deposited ◽  
Gas Flow Ratio

AbstractStress in plasma enhanced chemical vapor deposited (PECVD) SiNx films on InP has been evaluated as a function of source gases (NH3 /SiH4 or N2/SiH4) and plasma operating frequency (high, » 1 MHz or low, « 1 MHz). All films were deposited at 300°C in the same parallel-plate, radial flow plasma reactor. Levels of stress in PECVD SiNx on InP within a continuous range from moderately high tensile (∼ 5 × 109 dyne cm−2) to very high compressive (2 × 1010 dyne cm−2 ) were obtained from appropriate choices of deposition parameters. Deposition from NH3/SiH4 at high frequency produces tensile stress, of magnitude increasing with NH3/SiH4 flow ratio. Deposition from N2/SiH4 at high frequency produces zero to low compressive stress. At low frequency compressive stress is always produced; for N2/SiH4 increasing the gas flow ratio from 25:1 to 500:1 reduces the compressive stress from 1.8 X 1010 to 7 × 108 dyne cm−2. The ability to vary the stress in a dielectric film of approximately constant chemical composition over such a broad range is beneficial for assessing the effects of stress on device performance.

Hydrogen Concentration Analysis in Pecvd and Rtcvd Silicon Nitride Thin Films and It's Impact on Device Performance

2001 ◽  
Vol 664 ◽  
Author(s):  
C. Y. Wang ◽  
E. H. Lim ◽  
H. Liu ◽  
J. L. Sudijono ◽  
T. C. Ang ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Threshold Voltage ◽  
Vapor Deposition ◽  
Gas Flow ◽  
Chemical Vapor ◽  
Gate Oxide ◽  
Nitride Film ◽  
Device Performance ◽  
Gas Flow Ratio ◽  
The Impact

ABSTRACTIn this paper the impact of the ESL (Etch Stop layer) nitride on the device performance especially the threshold voltage (Vt) has been studied. From SIMS analysis, it is found that different nitride gives different H concentration, [H] in the Gate oxide area, the higher [H] in the nitride film, the higher H in the Gate Oxide area and the lower the threshold voltage. It is also found that using TiSi instead of CoSi can help to stop the H from diffusing into Gate Oxide/channel area, resulting in a smaller threshold voltage drift for the device employed TiSi. Study to control the [H] in the nitride film is also carried out. In this paper, RBS, HFS and FTIR are used to analyze the composition changes of the SiN films prepared using Plasma enhanced Chemical Vapor deposition (PECVD), Rapid Thermal Chemical Vapor Deposition (RTCVD) with different process parameters. Gas flow ratio, RF power and temperature are found to be the key factors that affect the composition and the H concentration in the film. It is found that the nearer the SiN composition to stoichiometric Si3N4, the lower the [H] in SiN film because there is no excess silicon or nitrogen to be bonded with H. However the lowest [H] in the SiN film is limited by temperature. The higher the process temperature the lower the [H] can be obtained in the SiN film and the nearer the composition to stoichiometric Si3N4.

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