In situ, real-time thickness measurement techniques for bath-deposited CdS thin films on Cu(In,Ga)Se2

AbstractThe formation and growth of Cu6Sn5 and Cu3Sn at the interface of Sn-Pb solder/copper substrate are factors which affect the solderability and reliability of electronic solder joints. The addition of particles such as Ni to eutectic Sn-Pb solder drastically affects the activation energies of formation for both intermetallics. This study was performed to understand the mechanisms of intermetallic formation and the effects of Ni on intermetallic growth. Cu/Sn and Cu/Sn/Ni thin films were deposited by evaporation and observed in the TEM in real time using a hot stage. The diffusion of Sn through Cu6Sn5 and Cu3Sn followed by reaction with Cu must occur for intermetallic formation and growth to take place. Ni is an effective diffusion barrier which prevents Sn from diffusing into Cu.

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Quantitative In-Situ Nanoindentation of Thin Films in a Transmission Electron Microscope

Microscopy and Microanalysis ◽

10.1017/s1431927600030634 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 912-913

Author(s):

A.M. Minorl ◽

E.A. Stach ◽

J.W. Morris

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Real Time ◽

Silicon Substrates ◽

Boron Doped Diamond ◽

Boron Doped ◽

Transmission Electron ◽

Diamond Indenter ◽

Force Calibration

A unique in situ nanoindentation stage has been built and developed at the National Center for Electron Microscopy in Berkeley, CA. By using piezoceramic actuators to finely position a 3-sided, boron-doped diamond indenter, we are able to image in real time the nanoindentation induced deformation of thin films. Recent work has included the force-calibration of the indenter, using silicon cantilevers to establish a relationship between the voltage applied to the piezoactuators, the displacement of the diamond tip, and the force generated.In this work, we present real time, in situ TEM observations of the plastic deformation of Al thin films grown on top of lithographically-prepared silicon substrates. The in situ nanoindentations require a unique sample geometry (see Figure 1) in which the indenter approaches the specimen normal to the electron beam. in order to meet this requirement, special wedge-shaped silicon samples were designed and microfabricated so that the tip of the wedge is sharp enough to be electron transparent.

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Direct quantitative imaging of the writing stage in a photosensitive azopolymer by digital holography

Soft Matter ◽

10.1039/c9sm01018a ◽

2019 ◽

Vol 15 (39) ◽

pp. 7809-7813 ◽

Cited By ~ 4

Author(s):

V. Pagliarulo ◽

A. Calabuig ◽

S. Grilli ◽

P. Ferraro

Keyword(s):

Thin Films ◽

Real Time ◽

Surface Relief ◽

Digital Holography ◽

Light Exposure ◽

Quantitative Imaging ◽

Continuous Light ◽

Full Field ◽

Surface Relief Grating

In this paper, we demonstrated that the gradual formation of a surface relief grating (SRG) in azopolymer thin films under continuous light exposure could be directly observed in situ and in real-time, allowing full-field characterization.

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Cadmium Sulfide Thin Films Deposited onto MWCNT/Polysulfone Substrates by Chemical Bath Deposition

Advances in Materials Science and Engineering ◽

10.1155/2016/2890717 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

M. Moreno ◽

G. M. Alonzo-Medina ◽

A. I. Oliva ◽

A. I. Oliva-Avilés

Keyword(s):

Thin Films ◽

Electric Field ◽

Cadmium Sulfide ◽

Chemical Bath Deposition ◽

Multiwall Carbon Nanotubes ◽

Low Concentrations ◽

Average Grain Size ◽

Cds Thin Films ◽

Current Electric Field

Cadmium sulfide (CdS) thin films were deposited by chemical bath deposition (CBD) onto polymeric composites with electric field-aligned multiwall carbon nanotubes (MWCNTs). MWCNT/polysulfone composites were prepared by dispersing low concentrations of MWCNTs within dissolved polysulfone (PSF). An alternating current electric field was “in situ” applied to align the MWCNTs within the dissolved polymer along the field direction until the solvent was evaporated. 80 μm thick solid MWCNT/PSF composites with an electrical conductivity 13 orders of magnitude higher than the conductivity of the neat PSF were obtained. The MWCNT/PSF composites were subsequently used as flexible substrates for the deposition of CdS thin films by CBD. Transparent and adherent CdS thin films with an average thickness of 475 nm were obtained. The values of the energy band gap, average grain size, rms roughness, crystalline structure, and preferential orientation of the CdS films deposited onto the polymeric substrate were very similar to the corresponding values of the CdS deposited onto glass (conventional substrate). These results show that the MWCNT/PSF composites with electric field-tailored MWCNTs represent a suitable option to be used as flexible conducting substrate for CdS thin films, which represents an important step towards the developing of flexible systems for photovoltaic applications.

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