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

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.

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

MRS Proceedings ◽

10.1557/proc-685-d5.7.1 ◽

2001 ◽

Vol 685 ◽

Cited By ~ 8

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.

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Hetero-Epitaxy of Group Va Metals on Sapphire

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095716 ◽

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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(111) Monocrystalline Nickel Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095819 ◽

1972 ◽

Vol 30 ◽

pp. 512-513

Author(s):

T.E. Pratt ◽

R.W. Vook

Keyword(s):

Film Thickness ◽

Deposition Rate ◽

Room Temperature ◽

Narrow Range ◽

High Vacuum ◽

Residual Pressure ◽

Temperature Dependent ◽

Deposition Parameters ◽

Transmission Electron ◽

Substrate Temperatures

(111) oriented thin monocrystalline Ni films have been prepared by vacuum evaporation and examined by transmission electron microscopy and electron diffraction. In high vacuum, at room temperature, a layer of NaCl was first evaporated onto a freshly air-cleaved muscovite substrate clamped to a copper block with attached heater and thermocouple. Then, at various substrate temperatures, with other parameters held within a narrow range, Ni was evaporated from a tungsten filament. It had been shown previously that similar procedures would yield monocrystalline films of CU, Ag, and Au.For the films examined with respect to temperature dependent effects, typical deposition parameters were: Ni film thickness, 500-800 A; Ni deposition rate, 10 A/sec.; residual pressure, 10-6 torr; NaCl film thickness, 250 A; and NaCl deposition rate, 10 A/sec. Some additional evaporations involved higher deposition rates and lower film thicknesses.Monocrystalline films were obtained with substrate temperatures above 500° C. Below 450° C, the films were polycrystalline with a strong (111) preferred orientation.

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Observations on the growth of YBa2Cu3O7-δ thin films on MgO by pulsed-laser ablation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089652 ◽

1991 ◽

Vol 49 ◽

pp. 1068-1069

Author(s):

M. Grant Norton ◽

C. Barry Carter

Keyword(s):

Thin Film ◽

Thin Films ◽

Laser Ablation ◽

Substrate Surface ◽

Pulsed Laser ◽

Pulsed Laser Ablation ◽

Thin Film Deposition ◽

Film Deposition ◽

Laser Ablation Process ◽

Deposition Parameters

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.

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Advances in Stem Instrumentation for Biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180562 ◽

1990 ◽

Vol 48 (1) ◽

pp. 362-363

Author(s):

J. S. Wall

Keyword(s):

Scanning Transmission Electron Microscope ◽

Carbon Films ◽

Specimen Preparation ◽

Material Deposition ◽

Active User ◽

Percent Improvement ◽

Scanning Transmission ◽

The Moment ◽

Film Substrate ◽

High Level

The forte of the Scanning transmission Electron Microscope (STEM) is high resolution imaging with high contrast on thin specimens, as demonstrated by visualization of single heavy atoms. of equal importance for biology is the efficient utilization of all available signals, permitting low dose imaging of unstained single molecules such as DNA.Our work at Brookhaven has concentrated on: 1) design and construction of instruments optimized for a narrow range of biological applications and 2) use of such instruments in a very active user/collaborator program. Therefore our program is highly interactive with a strong emphasis on producing results which are interpretable with a high level of confidence.The major challenge we face at the moment is specimen preparation. The resolution of the STEM is better than 2.5 A, but measurements of resolution vs. dose level off at a resolution of 20 A at a dose of 10 el/A2 on a well-behaved biological specimen such as TMV (tobacco mosaic virus). To track down this problem we are examining all aspects of specimen preparation: purification of biological material, deposition on the thin film substrate, washing, fast freezing and freeze drying. As we attempt to improve our equipment/technique, we use image analysis of TMV internal controls included in all STEM samples as a monitor sensitive enough to detect even a few percent improvement. For delicate specimens, carbon films can be very harsh-leading to disruption of the sample. Therefore we are developing conducting polymer films as alternative substrates, as described elsewhere in these Proceedings. For specimen preparation studies, we have identified (from our user/collaborator program ) a variety of “canary” specimens, each uniquely sensitive to one particular aspect of sample preparation, so we can attempt to separate the variables involved.

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