Interface characterization of PICVD-coated polymer substrates

The binding structure in the interface region oxide film/polymer has been investigated by means of XPS and is correlated with the adhesion obtained by a Pull Test. Polycarbonate (PC) and diethyleneglycol-bisallylcarbonate (CR39) are employed as substrate and SiO_xC_yH_z-films are deposited by using a pulsed microwave plasma deposition process (PICVD). Best adhesion is obtained by pretreatment of the substrate surface with an O₂-plasma which increases the O/C ratio, in combination with a PICVD-process with low precursor content. Received: 27 July 1996 / Revised: 13 January 1997 / Accepted: 18 January 1997     

Elastic electron scattering from 3He and 4He

The cross sections for elastic electron scattering from ³He and ⁴He were measured for the momentum transfer range from 0.45–2.0 fm^?1. The cross sections were separated into their longitudinal (charge) and transverse (magnetic) contributions using the Rosenbluth formula. The charge and magnetic form factors were obtained model-independently.The rms charge radii were found to be 1.671 (14) fm for ⁴He and 1.976 (15) fm for ³He, and the magnetic rms radius of ³He is 1.99 (6) fm. The mis charge radius for ⁴He is in excellent agreement with the latest muonic data.Comparison of the form factors was made with Faddeev three-body calculations using realistic two-body NN interactions. At present the theoretical calculation is not able to reproduce the experimental data.     

Electrodisintegration of 3He

Double differential cross sections for electron-³He scattering leading to continuum states were measured between break-up threshold and the region of quasi-free interaction in a momentum transfer range of $\text{1}\text{fm}{}^{\mathrm{?2}}\text{< ¦}\text{q}\text{¦}{}^2\text{< 2.5}\text{fm}{}^{\mathrm{?2}}$. The cross sections for the quasi-free scattering calculated in plane-wave impulse approximation were found to be in good agreement with the experimental results for momentum transfer $\text{¦}\text{q}\text{¦ > 1.5}\text{fm}{}^{\mathrm{?1}}$.     

Density and Young’s modulus of thin TiO2 films

Densities, ρ, of thin TiO₂ layers, produced by reactive evaporation (RE) and ion plating (IP) have been analyzed by means of grazing incidence X-ray reflectometry (GIXR). Depending on the deposition conditions, the layers are amorphous or polycrystalline, with densities between 2.9 g/cm³ and 3.9 g/cm³. Young’s moduli, E, have been analyzed for 280 nm and 500 nm thick layers by means of surface acoustic wave spectroscopy (SAWS) and vary between 65 GPa for RE films and 147 GPa for IP layers. The values are independent of film thickness, but correlate with the density. A phase transition of the TiO₂ films from the amorphous state to anatase occurs at temperatures above 210°C and increases the Young’s modulus significantly, whereas the density remains unchanged.     

Elastic electron scattering from 40Ar

Cross sections for elastic electron scattering from ⁴⁰Ar have been measured for the momentum transfer range from 0.59 to 1.31 fm^?1. We have analyzed with the Fourier-Bessel ansatz our data as well as the data of former experiments. The rms charge radius we have found is 3.423(14) fm. The results are in excellent agreement with latest muonic data. Furthermore, we have reanalyzed former ⁴⁰Ca data and have discussed the ⁴⁰Ca- ⁴⁰Ar charge distribution.     

Residual Stresses from Incremental Hole Drilling Using Directly Deposited Thin Film Strain Gauges

Experimental Mechanics - Commonly, polymer foil-based strain gauges are used for the incremental hole drilling method to obtain residual stress depth profiles. These polymer foil-based strain...     

Excitation of the quasi-bound state in 4He by electron scattering at medium momentum transfer

The cross sections of inelastic electron scattering on ⁴He leading to the quasi-bound state (0⁺, ε = 20.1 MeV) were measured in the momentum transfer range 0.8 fm^?2 < q² < 2.4 fm^?2. We found it to be a pure longitudinal transition and give the form factor of this C0transition.