A two-step UV curing process for producing high tensile stressed silicon nitride layers

ABSTRACTThis experimental study presents a comparison of differently tensile stressed silicon nitride (SiN) layers and their response to irradiation in a vacuum ultraviolet (VUV) curing system. Therefore, three types of silicon nitride with initial stress levels of 450 MPa, 700 MPa and 980 MPa were deposited by plasma enhanced chemical vapor deposition (PECVD). In contrast to industrial standard VUV curing with broadband lamps ≥ 220 nm radiation wavelengths, we analyzed the effects of curing with single wavelengths at 172 nm and 222 nm. The samples were characterized by Fourier Transform Infrared Spectroscopy, ellipsometry, and wafer bow measurement. It could be shown that high energy photons are able to dehydrogenize SiN films more than lower energetic photons compared with lower Si-N-Si crosslinking effects. Furthermore, we could show that a dual combined 172 nm and 222 nm VUV curing procedure can produce films with very low hydrogen concentration and high percentage of structural units consisting of Si-N-Si bonds. In conclusion of this study, an up to +900 MPa stress increasing process could be established.

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Control of a Robotic UV Curing Process With Thermal Vision Feedback Through Two IR Cameras

Volume 10: Mechanical Systems and Control, Parts A and B ◽

10.1115/imece2009-13007 ◽

2009 ◽

Author(s):

Fan Zeng ◽

Beshah Ayalew ◽

Mohammed Omar

Keyword(s):

Control Variable ◽

Ultra Violet ◽

Uv Curing ◽

High Energy ◽

Curing Process ◽

Radiant Intensity ◽

Loop Control ◽

Thermal Vision ◽

Uv Curing Process ◽

Vision Feedback

Robotic ultra-violet (UV) curing is considered to be one of the effective ways to replace the current convection-based methods in various manufacturing processes due to its fast curing rate and high energy efficiency. This paper presents a closed-loop control of a robotic UV curing system by using thermal vision feedback through two infrared (IR) cameras. The proposed approach is developed based on a mathematical analysis of the fundamental UV curing process and the integration of the local and global IR cameras in a cascade manner. A computer simulation study is conducted to evaluate the proposed strategy by regarding two control variables: the radiant intensity of the UV heater and the sweeping speed of the robot end effector. The results indicate that controllers using either control variable can compensate for interferences and improve curing quality under this thermal-vision-based architecture.

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Si3 N4/SiO2 Multi-Layer Reflecting Stacks for Photonic Switching Applications

MRS Proceedings ◽

10.1557/proc-298-223 ◽

1993 ◽

Vol 298 ◽

Author(s):

D.J. Stephens ◽

S.S. He ◽

G. Lucovsky ◽

H. Mikkelsen ◽

K. Leo

Keyword(s):

Optical Properties ◽

Periodic Structures ◽

Chemical Vapor ◽

Optical Path Length ◽

High Energy ◽

Fused Silica ◽

Nitride Film ◽

Photonic Switching ◽

Model Calculations ◽

Nitride Layers

AbstractWe have fabricated stacked-structures comprised of i) fused silica substrates, and ii) near-periodic Si3N4/SiO2 bi-layers by low-temperature, 250°C, remote plasmaenhanced chemical-vapor deposition. Comparing the reflectance of these structures with model calculations, we have been able to identify the effects on the reflectance spectra of departures from i) exact periodicity, ii) not having the constituent dielectric layers each posses an ideal optical path length, OPL, exactly equal to λcentral/4, and iii) the intrinsic dispersion in the dielectric functions of the oxide and nitride materials. We have prepared quasi-periodic structures in which the OPL of the higher index Si3N4 layer was > λcentral/4, and in which the OPL of the lower index SiO2 layer was < λcentral/4. This promotes a second strong reflectance band at an energy that is approximately two times that of the primary band. Calculations have shown that the reflectance values in this band, and near a reflectance minimum on the high energy side of the band, are both very sensitive to changes in the optical properties of the nitride film. We present calculations that demonstrate the effects on the reflectance of this band by a temperature-induced modulation of the optical properties of the oxide and nitride layers.

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Hypothetic impact of chemical bonding on the moisture resistance of amorphous SixNyHz by plasma-enhanced chemical vapor deposition

Metallurgical Research & Technology ◽

10.1051/metal/2018072 ◽

2018 ◽

Vol 115 (4) ◽

pp. 406

Author(s):

Catheline Cazako ◽

Karim Inal ◽

Alain Burr ◽

Frederic Georgi ◽

Rodolphe Cauro

Keyword(s):

Activation Energy ◽

Water Vapor ◽

Silicon Nitride ◽

Silicon Dioxide ◽

Dissolution Rate ◽

Liquid Water ◽

Chemical Vapor ◽

Rate Of Dissolution ◽

Liquid States ◽

Nitride Layers

The relationship between the microstructure of silicon nitride and its sensitivity to moisture was studied. The effectiveness of Si-H rich and N-H rich silicon nitride layers was measured under attack from water in vapor and liquid states. For water vapor attack, samples are exposed to vapor at 85 °C with a relative humidity of 85% during 1600 hours; for liquid water attack, samples are dipped in water at 60, 85 and 100 °C for 200 hours. The water resistance of the Si-H rich and N-H rich silicon nitride layers was evaluated by measuring: (i) the thickness of the silicon dioxide formed after their oxidation with water vapor, (ii) the rate of dissolution of the silicon nitride in liquid water and (iii) the corresponding activation of energy. This evaluation was performed by coupling spectroscopic ellipsometry, infra-red and X-ray photoelectron spectrometry analyses. The results revealed that for Si-H rich layer, 10 nm of silicon dioxide was formed during the water vapor attack; for liquid water attack, a high activation energy (0.88 eV) and a low dissolution rate were observed regardless of the water temperature. For N-H rich layers, approximatively 6–8 nm of silicon dioxide was formed and a low activation energy (0.64 eV) with a high dissolution rate were observed. All of these observations lead to the conclusion that the N-H rich layers could be less resistant to moisture because the isoelectronic relationship between Si2N-H and −H2O+ facilitated their deterioration in water. Moreover, a higher rate of nanoporosity for N-H rich layers than Si-H rich layer could complete this hypothesis.

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Improvement in Gate Dielectric Quality of Ultra Thin a: SiN:H MNS Capacitor by Hydrogen Etching of the Substrate

MRS Proceedings ◽

10.1557/proc-716-b4.8 ◽

2002 ◽

Vol 716 ◽

Author(s):

Parag C. Waghmare ◽

Samadhan B. Patil ◽

Rajiv O. Dusane ◽

V.Ramgopal Rao

Keyword(s):

Silicon Nitride ◽

Gate Dielectric ◽

Substrate Surface ◽

Scaling Limit ◽

Tunneling Current ◽

Chemical Vapor ◽

Poor Performance ◽

State Density ◽

Direct Tunneling Current

AbstractTo extend the scaling limit of thermal SiO2, in the ultra thin regime when the direct tunneling current becomes significant, members of our group embarked on a program to explore the potential of silicon nitride as an alternative gate dielectric. Silicon nitride can be deposited using several CVD methods and its properties significantly depend on the method of deposition. Although these CVD methods can give good physical properties, the electrical properties of devices made with CVD silicon nitride show very poor performance related to very poor interface, poor stability, presence of large quantity of bulk traps and high gate leakage current. We have employed the rather newly developed Hot Wire Chemical Vapor Deposition (HWCVD) technique to develop the a:SiN:H material. From the results of large number of optimization experiments we propose the atomic hydrogen of the substrate surface prior to deposition to improve the quality of gate dielectric. Our preliminary results of these efforts show a five times improvement in the fixed charges and interface state density.

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Nanostructured powders based on aluminum reinforced by silicon nitride designed for spraying of multifunctional strengthened coatings

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2019-97-1-65-73 ◽

2019 ◽

pp. 65-73

Author(s):

T. I. Bobkova ◽

B. V. Farmakovsky ◽

N. A. Sokolova

Keyword(s):

Silicon Nitride ◽

Composite Powder ◽

High Energy ◽

Cold Gas Dynamic Spraying ◽

Powder Materials ◽

Structure And Properties ◽

Gas Dynamic ◽

Composition Structure ◽

New Phase ◽

Nanostructured Powders

The work deals with topical issues such as development of composite nanostructured powder materials. The results of creating powders based on the system “aluminum–nitride of silicon” are presented. Complex investigations of the composition, structure and properties of powder materials, as well as coatings formed on their basis by supersonic cold gas dynamic spraying, were carried out. It has been found that the high-energy treatment of a powder mixture of aluminum with nanofibers of silicon nitride provides the formation of a composite powder in which a new phase of the Si(1-х)AlхO(1-х)Nх type is formed, which additionally increases the hardness in the coatings to be sprayed.

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Low-Temperature Formation of SiNx Gate Insulator for Thin-Film Transistor Using CAT-CVD Method

MRS Proceedings ◽

10.1557/proc-508-151 ◽

1998 ◽

Vol 508 ◽

Author(s):

A. Izumi ◽

T. Ichise ◽

H. Matsumura

Keyword(s):

Thin Film ◽

Chemical Vapor Deposition ◽

Silicon Nitride ◽

Vapor Deposition ◽

Thin Film Transistors ◽

Chemical Vapor ◽

State Density ◽

Gate Insulator ◽

Catalytic Chemical Vapor Deposition ◽

Silicon Nitride Films

AbstractSilicon nitride films prepared by low temperatures are widely applicable as gate insulator films of thin film transistors of liquid crystal displays. In this work, silicon nitride films are formed around 300 °C by deposition and direct nitridation methods in a catalytic chemical vapor deposition system. The properties of the silicon nitride films are investigated. It is found that, 1) the breakdown electric field is over 9MV/cm, 2) the surface state density is about 1011cm−2eV−1 are observed in the deposition films. These result shows the usefulness of the catalytic chemical vapor deposition silicon nitride films as gate insulator material for thin film transistors.

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Effect of Thermal Annealing on the Photoluminescence of Dense Si Nanodots Embedded in Amorphous Silicon Nitride Films

Micromachines ◽

10.3390/mi12040354 ◽

2021 ◽

Vol 12 (4) ◽

pp. 354

Author(s):

Qianqian Liu ◽

Xiaoxuan Chen ◽

Hongliang Li ◽

Yanqing Guo ◽

Jie Song ◽

...

Keyword(s):

Silicon Nitride ◽

Amorphous Silicon ◽

Thermal Annealing ◽

Chemical Vapor ◽

Peak Position ◽

Excitation Wavelength ◽

Very High Frequency ◽

Amorphous Silicon Nitride ◽

Silicon Nitride Films ◽

High Frequency Plasma

Luminescent amorphous silicon nitride-containing dense Si nanodots were prepared by using very-high-frequency plasma-enhanced chemical vapor deposition at 250 °C. The influence of thermal annealing on photoluminescence (PL) was studied. Compared with the pristine film, thermal annealing at 1000 °C gave rise to a significant enhancement by more than twofold in terms of PL intensity. The PL featured a nanosecond recombination dynamic. The PL peak position was independent of the excitation wavelength and measured temperatures. By combining the Raman spectra and infrared absorption spectra analyses, the enhanced PL was suggested to be from the increased density of radiative centers related to the Si dangling bonds (K0) and N4+ or N20 as a result of bonding configuration reconstruction.

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Research on Sapphire Deep Cavity Corrosion and Mask Selection Technology

Micromachines ◽

10.3390/mi12020136 ◽

2021 ◽

Vol 12 (2) ◽

pp. 136

Author(s):

Yiingqi Shang ◽

Hongquan Zhang ◽

Yan Zhang

Keyword(s):

Silicon Nitride ◽

Silicon Dioxide ◽

Chemical Vapor ◽

Nitride Layer ◽

Wet Etching ◽

Silicon Dioxide Layer ◽

Etching Depth ◽

Deep Cavity ◽

Mask Layer ◽

Layer Composite

Aimed at the problem of the small wet etching depth in sapphire microstructure processing technology, a multilayer composite mask layer is proposed. The thickness of the mask layer is studied, combined with the corrosion rate of different materials on sapphire in the sapphire etching solution, different mask layers are selected for the corrosion test on the sapphire sheet, and then the corrosion experiment is carried out. The results show that at 250 °C, the choice is relatively high when PECVD (Plasma Enhanced Chemical Vapor Deposition) is used to make a double-layer composite film of silicon dioxide and silicon nitride. When the temperature rises to 300 °C, the selection ratio of the silicon dioxide layer grown by PECVD is much greater than that of the silicon nitride layer. Therefore, under high temperature conditions, a certain thickness of silicon dioxide can be used as a mask layer for deep cavity corrosion.

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