Fabrication of thin‐wall, freestanding inertial confinement fusion targets by chemical vapor deposition

Thickness measurements of thin films are performed by both energy-dispersive x-ray spectroscopy (EDS) and x-ray fluorescence (XRF). XRF can measure thicker films than EDS, and XRF measurements also have somewhat greater precision than EDS measurements. However, small components with curved or irregular shapes that are used for various applications in the the Inertial Confinement Fusion program at LLNL present geometrical problems that are not conducive to XRF analyses but may have only a minimal effect on EDS analyses. This work describes the development of an EDS technique to measure the thickness of electroless nickel deposits on gold substrates. Although elaborate correction techniques have been developed for thin-film measurements by x-ray analysis, the thickness of electroless nickel films can be dependent on the plating bath used. Therefore, standard calibration curves were established by correlating EDS data with thickness measurements that were obtained by contact profilometry.

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In situ study of electron beam-induced chemical vapor deposition of Au in an environmental TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137653 ◽

1995 ◽

Vol 53 ◽

pp. 256-257

Author(s):

J. Drucker ◽

R. Sharma ◽

J. Kouvetakis ◽

K.H.J. Weiss

Keyword(s):

Electron Beam ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Quantum Effect ◽

Line Drawing ◽

Chemical Vapor ◽

Environmental Cell ◽

Engineering Changes ◽

Kinetics Of

Patterning of metals is a key element in the fabrication of integrated microelectronics. For circuit repair and engineering changes constructive lithography, writing techniques, based on electron, ion or photon beam-induced decomposition of precursor molecule and its deposition on top of a structure have gained wide acceptance Recently, scanning probe techniques have been used for line drawing and wire growth of W on a silicon substrate for quantum effect devices. The kinetics of electron beam induced W deposition from WF6 gas has been studied by adsorbing the gas on SiO2 surface and measuring the growth in a TEM for various exposure times. Our environmental cell allows us to control not only electron exposure time but also the gas pressure flow and the temperature. We have studied the growth kinetics of Au Chemical vapor deposition (CVD), in situ, at different temperatures with/without the electron beam on highly clean Si surfaces in an environmental cell fitted inside a TEM column.

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The relaxation of compressive biaxial strains in SOS via microtwins

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155013 ◽

1989 ◽

Vol 47 ◽

pp. 608-609

Author(s):

M. E. Twigg ◽

E. D. Richmond ◽

J. G. Pellegrino

Keyword(s):

Thin Film ◽

Chemical Vapor Deposition ◽

Molecular Beam Epitaxy ◽

Compressive Stress ◽

Vapor Deposition ◽

Partial Dislocation ◽

Molecular Beam ◽

Volume Fraction ◽

Chemical Vapor ◽

Silicon Thin Film

For heteroepitaxial systems, such as silicon on sapphire (SOS), microtwins occur in significant numbers and are thought to contribute to strain relief in the silicon thin film. The size of this contribution can be assessed from TEM measurements, of the differential volume fraction of microtwins, dV/dν (the derivative of the microtwin volume V with respect to the film volume ν), for SOS grown by both chemical vapor deposition (CVD) and molecular beam epitaxy (MBE).In a (001) silicon thin film subjected to compressive stress along the [100] axis , this stress can be relieved by four twinning systems: a/6[211]/( lll), a/6(21l]/(l1l), a/6[21l] /( l1l), and a/6(2ll)/(1ll).3 For the a/6[211]/(1ll) system, the glide of a single a/6[2ll] twinning partial dislocation draws the two halves of the crystal, separated by the microtwin, closer together by a/3.

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