Using Statistical Methods to Optimize Patterning Parameters for Tungsten Deposition

2007 ◽  
Author(s):  
Michael DiBattista ◽  
Kimball Skinner ◽  
Rick Kneedler ◽  
Leonid Vasilvey ◽  
Lukas Drybcak ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Statistical Methods ◽  
Deposition Rates ◽  
Low Resistivity ◽  
Material Deposition ◽  
Deposition Parameters ◽  
Beam Parameters

Abstract Circuit edit and failure analysis require tungsten deposition parameters to accomplish different goals. Circuit edit applications desire low resistivity values for rewiring, while failure analysis requires high deposition rates for capping layers. Tungsten deposition can be a well controlled process for a variety of beam parameters. For circuit edit, tungsten resistivity approaching below 150 µohm-cm and 50 μm3/nC is predicted. Material deposition rates of 80 μm3/nC can be achieved with reasonable pattern accuracy using defocus as a parameter.

scholarly journals Investigation of High-Depostition-Rate Additive Manufacturing of Ti-6Al-4V via Laser Material Deposition

2021 ◽  
Author(s):  
Rebar Hama-Saleh ◽  
Kerim Yildirim ◽  
Susanne Hemes ◽  
Andreas Weisheit ◽  
Constantin Leon Häfner
Keyword(s):  
Additive Manufacturing ◽  
Hot Forging ◽  
Scanning Speed ◽  
Inert Atmosphere ◽  
High Deposition Rate ◽  
Beam Diameter ◽  
Deposition Rates ◽  
Laser Material ◽  
Aerospace Applications ◽  
Material Deposition

Ti-6Al-4V is the most prominent titanium alloy widely used e.g. for aerospace applications. Conventionally, many Ti-6Al-4V aerospace components are produced by a multi-stage hot forging process followed by subsequent machining which often generates a high amount of scrap. Additive manufacturing (AM), such as powder-based laser material deposition (p-LMD), enables parts to be made with geometric freedom and near-net-shape, but so far lacks high deposition rates. The present study proposes high-deposition-rate laser material deposition manufacturing using a large laser beam diameter and increased scanning speed to achieve deposition rates up to 5 kg/h. As Ti-6Al-4V is prone to oxygen pick-up, the process was performed in an inert atmosphere. We determined suitable process windows for tracks without fusion defects and low porosity and investigated microstructure and hardness.

Microcrystalline Silicon for Solar Cells at High Deposition Rates by Hot Wire Cvd

2002 ◽  
Vol 715 ◽  
Author(s):  
R. E. I. Schropp ◽  
Y. Xu ◽  
E. Iwaniczko ◽  
G. A. Zaharias ◽  
A. H. Mahan
Keyword(s):  
Solar Cells ◽  
Substrate Temperature ◽  
Volume Fraction ◽  
Silicon Layer ◽  
Hot Wire ◽  
Crystalline Volume Fraction ◽  
Microcrystalline Silicon ◽  
Deposition Rates ◽  
Deposition Parameters ◽  
Si Films

AbstractWe have explored which deposition parameters in Hot Wire CVD have the largest impact on the quality of microcrystalline silicon (μc-Si) made at deposition rates (Rd) < 10 Å/s for use in thin film solar cells. Among all parameters, the filament temperature (Tfil) appears to be crucial for making device quality films. Using two filaments and a filament-substrate spacing of 3.2 cm, μc-Si films, using seed layers, can be deposited at high Tfil (∼2000°C) with a crystalline volume fraction < 70-80 % at Rd's < 30 Å/s. Although the photoresponse of these layers is high (< 100), they appear not to be suitable for incorporation into solar cells, due to their porous nature. n-i-p cells fabricated on stainless steel with these i-layers suffer from large resistive effects or barriers, most likely due to the oxidation of interconnected pores in the silicon layer. The porosity is evident from FTIR measurements showing a large oxygen concentration at ∼1050 cm-1, and is correlated with the 2100 cm-1 signature of most of the Si-H stretching bonds. Using a Tfil of 1750°C, however, the films are more compact, as seen from the absence of the 2100 cm-1 SiH mode and the disappearance of the FTIR Si-O signal, while the high crystalline volume fraction (< 70-80 %) is maintained. Using this Tfil and a substrate temperature of 400°C, we obtain an efficiency of 4.9 % for cells with a Ag/ZnO back reflector, with an i-layer thickness of only ∼0.7 μm. High values for the quantum efficiency extend to very long wavelengths, with values of 33 % at 800 nm and 15 % at 900 nm, which are unequalled by a-SiGe:H alloys. Further, by varying the substrate temperature to enable deposition near the microcrystalline to amorphous transition (‘edge’) and incorporating variations in H2 dilution during deposition of the bulk, efficiencies of 6.0 % have been obtained. The Rd's of these i-layers are 8-10 Å/s, and are the highest to date obtained with HWCVD for microcrystalline layers used in cells with efficiencies of ∼6 %.

The preparation and some properties of low resistivity Zn3P2 films prepared using a hot-wall deposition method

1989 ◽  
Vol 67 (9) ◽  
pp. 893-895 ◽  
Author(s):  
A. Haque ◽  
D. E. Brodie
Keyword(s):  
Schottky Barrier ◽  
Deposition Method ◽  
Low Resistivity ◽  
Hole Trapping ◽  
Wall Deposition ◽  
Deposition Parameters

Low resistivity (100 Ω cm) films of polycrystalline Zn3P2 have been prepared by a hot-wall technique. The films are made up of randomly oriented crystals about 5 μm across. Films from 4 to 30 μm thick have been studied and a range of deposition parameters have been investigated. Doping densities of 1016/cm3 were achieved and three-hole trapping levels (near 0.37, 0.42, and 0.77 eV) were detected in Schottky barrier devices fabricated using these films.

Untersuchungen zur Epitaxie dünner Goldaufdampfschichten auf Alkalihalogeniden im Ultrahochvakuum

1968 ◽  
Vol 23 (10) ◽  
pp. 1526-1536 ◽  
Author(s):  
R. W. Adam
Keyword(s):  
Substrate Temperature ◽  
Crystal Orientation ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Gold Films ◽  
Oriented Growth ◽  
Deposition Rates ◽  
Deposition Parameters ◽  
Temperature Deposition ◽  
Substrate Temperatures

In the present paper the oriented growth of gold on alkalihalides, cleaved in ultra high vacuum has been investigated. The dependence of the crystal orientation on the deposition parameters substrate temperature, deposition rate, and the physical properties of the substrate were studied systematically. At suitable substrate temperatures and deposition rates it was possible to obtain epitaxial gold films on KCl, KBr and KJ.

scholarly journals Adaptation of material deposition parameters to account for out-time effects on prepreg tack

2020 ◽  
Vol 133 ◽  
pp. 105835
Author(s):  
A.W. Smith ◽  
A. Endruweit ◽  
G.Y.H. Choong ◽  
D.S.A. De Focatiis ◽  
P. Hubert
Keyword(s):  
Time Effects ◽  
Material Deposition ◽  
Deposition Parameters

A SIMULATION STUDY OF DEPOSITION PARAMETERS FOR 129I DISCHARGED FROM THE ROKKASHO REPROCESSING PLANT

2019 ◽  
Vol 184 (3-4) ◽  
pp. 376-379 ◽  
Author(s):  
Koichi Abe ◽  
Hidenao Hasegawa ◽  
Naofumi Akata ◽  
Hideki Kakiuchi ◽  
Jing-Hsien Chiang ◽  
...  
Keyword(s):  
Nuclear Fuel ◽  
Spent Nuclear Fuel ◽  
Mesoscale Model ◽  
Deposition Rates ◽  
Test Operation ◽  
Deposition Parameters ◽  
Penn State ◽  
Atmospheric Discharge ◽  
Atmospheric Concentrations ◽  
Reprocessing Plant

Abstract The first commercial spent nuclear fuel reprocessing plant at Rokkasho in Japan discharged 129I from actual spent nuclear fuel into the atmosphere during its test operation from 2006 to 2008. Previously, we measured monthly atmospheric concentrations of gaseous and particulate 129I and atmospheric deposition rates of 129I from the campus of our institute, which is 2.6 km east of the main stack of the plant. In this study, we simulated the atmospheric concentrations and deposition rates of 129I using a combination of the Fifth-Generation Penn State/NCAR Mesoscale Model and the improved CG-MATHEW/ADPIC models, Version 5.0. Here, we report on the optimised deposition parameters of 129I used to simulate the measured values using 129I atmospheric discharge rates from the main stack.

Epitaxial Planarization Using Ion Beam Assisted Deposition

1993 ◽  
Vol 316 ◽  
Author(s):  
Bertha P. Chang ◽  
Neville Sonnenberg ◽  
Paul C. McIntyre ◽  
Michael J. Cima ◽  
Jonathan Z. Sun ◽  
...  
Keyword(s):  
Thin Films ◽  
Pole Figure ◽  
Ion Beam ◽  
Normal Incidence ◽  
X Ray Diffraction ◽  
Deposition Rates ◽  
Atom Ratio ◽  
X Ray ◽  
Ion Beam Assisted Deposition ◽  
Beam Parameters

ABSTRACTCeO2 thin films have been deposited on patterned (100) LaAlO3 substrates using ion beam assisted deposition (IBAD) with ion beam energies between 350 and 500eV. Deposition temperatures were varied between 400°C and 600°C and deposition rates from 0.2Å/s to 1.2Å/s. Both normal and off-normal incidence ion bombardment have been studied. A trend towards planarization is observed when the ion to atom ratio is adjusted to obtain the proper degree of etching. The planarization mechanism for normal incidence bombardment appears to be similar to that previously observed for bias sputtering. X-ray diffraction shows that an initial layer of evaporated epitaxial CeO2 is required for continued epitaxial development during IBAD processing. The extent of planarization via off-normal ion incidence can be related to the direction of the ion beam with respect to the patterned features. X-ray pole figure measurements show that these films possess an in-plane orientation that is directly related to the ion beam parameters.

Polycrystalline Lead Iodide Films: Optical, Electrical and X-ray Counting Characterization

2001 ◽  
Vol 685 ◽  
Author(s):  
L. Fornaro ◽  
E. Saucedo ◽  
L. Mussio ◽  
A. Gancharov ◽  
F. Guimaraes ◽  
...  
Keyword(s):  
Physical Vapor Deposition ◽  
Peak Position ◽  
Polycrystalline Films ◽  
Lead Iodide ◽  
X Ray ◽  
Force Microscopy ◽  
Material Deposition ◽  
Deposition Parameters ◽  
Average Grain Size ◽  
Alternative Materials

AbstractLead iodide purified by zone refining and repeated sublimation was used for growing Polycrystalline films by physical vapor deposition. Palladium film was deposited as rear contact onto glass and alumina substrates 2.5 × 2.5 cm2 in size. Onto it, lead iodide polycrystalline films were grown by sublimation at 390 °C and 5 × 10−5 mm Hg, substrate temperatures of about 200 °C and deposition times of about 10 days. Film thickness was measured by X-ray transmission at 59.5 keV giving values from 35 to 50 μm (5%). Optical and atomic force microscopy were performed to the films giving an average grain size of (80±20) μm. Low temperature photoluminescence was performed and peak position and broadness confirmed the high purity of starting materials. Films were characterized by X-ray diffraction, giving an [ΣI (0 0 l)] / [ΣI (h k l)] relation of 0.8 that indicates a strong growth preferred orientation along c axis. Front palladium thermal deposition contacts and acrylic encapsulation were done and apparent resistivity (2 × 1014 Ω. cm) and current density (7 pA/cm2 (30 V)) were obtained. X-ray film response was checked by irradiating with 241Am and an X-ray beam. Finally, film and detector characterizations were correlated with starting material, deposition parameters and previous results for the same and alternative materials like mercuric iodide.

Statistics and parallaxes

1978 ◽  
Vol 48 ◽  
pp. 7-29
Author(s):  
T. E. Lutz
Keyword(s):  
Experimental Design ◽  
Statistical Methods ◽  
Review Paper ◽  
Systematic Errors ◽  
Past Experience ◽  
Random Errors ◽  
Trigonometric Parallaxes ◽  
Systematic And Random Errors

This review paper deals with the use of statistical methods to evaluate systematic and random errors associated with trigonometric parallaxes. First, systematic errors which arise when using trigonometric parallaxes to calibrate luminosity systems are discussed. Next, determination of the external errors of parallax measurement are reviewed. Observatory corrections are discussed. Schilt’s point, that as the causes of these systematic differences between observatories are not known the computed corrections can not be applied appropriately, is emphasized. However, modern parallax work is sufficiently accurate that it is necessary to determine observatory corrections if full use is to be made of the potential precision of the data. To this end, it is suggested that a prior experimental design is required. Past experience has shown that accidental overlap of observing programs will not suffice to determine observatory corrections which are meaningful.

Hetero-Epitaxy of Group Va Metals on Sapphire

1972 ◽  
Vol 30 ◽  
pp. 492-493
Author(s):  
J. E. O'Neal ◽  
J. J. Bellina ◽  
B. B. Rath
Keyword(s):  
Thermal Contact ◽  
High Vacuum ◽  
Electron Beam Evaporation ◽  
Ultra High Vacuum ◽  
Backing Plate ◽  
Sapphire Substrates ◽  
Deposition Parameters ◽  
Polishing Damage ◽  
Reflection Electron Diffraction

Thin films of the bcc metals vanadium, niobium and tantalum were epitaxially grown on (0001) and sapphire substrates. Prior to deposition, the mechanical polishing damage on the substrates was removed by an in-situ etch. The metal films were deposited by electron-beam evaporation in ultra-high vacuum. The substrates were heated by thermal contact with an electron-bombarded backing plate. The deposition parameters are summarized in Table 1.The films were replicated and examined by electron microscopy and their crystallographic orientation and texture were determined by reflection electron diffraction. Verneuil-grown and Czochralskigrown sapphire substrates of both orientations were employed for each evaporation. The orientation of the metal deposit was not affected by either increasing the density of sub-grain boundaries by about a factor of ten or decreasing the deposition rate by a factor of two. The results on growth epitaxy are summarized in Tables 2 and 3.

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