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We report room temperature delamination of chemically vapor deposited diamond films on a Si substrate due to 1.5 MeV He[sup +] ion bombardment. The delamination of films has been studied by scanning electron microscopy. The threshold fluence at which the delamination takes place has been determined in situ by monitoring the hydrogen signal with the help of elastic recoil detection analysis. Micro Raman measurements show the presence of residual stress (1.19 GPa) in the as-prepared films and its relaxation at the peripheri of the delaminated regions. It is proposed that enhancement of the residual stress during He[sup +] ion bombardment leads to stress saturation conditions which result in the delamination of the brittle diamond films from the film/substrate interface. These findings lead to the possibility of creating ion-beam induced channels in diamond films for device isolation by suitable choice of film/substrate combination. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the room-temperature synthesis of copper germanide by ion beam mixing. Details on the resistivity of the mixed compounds; Information on the phase formation of the compounds; Information on the dominant moving species controlling phase formation; Explanation of the phase formation sequence.

Chemically textured Si with improved absorption in the complete range of solar spectrum is investigated by ultraviolet/visible/near-infrared (UV/Vis/NIR) spectroscopy, showing an average specular reflectance of ~0.4% in the wavelength of 500-3000nm. The pyramidal structures on such solar-blind Si can reduce the reflectance further below 0.1% in the UV region by conformal growth of granular Al-doped ZnO (AZO) films. X-ray diffraction analyses suggest the growth of polycrystalline AZO on faceted-Si. Moreover, marginal increase in electrical conductivity of AZO is found on textured surfaces, whereas rise in leakage current in Schottky-like Ag/AZO/Si/Ag heterostructure devices is noticed with increasing Si surface area. [ABSTRACT FROM AUTHOR]

In this letter, the authors report the correlation between the magnetic and the structural properties of 200 keV Kr and 50 keV Ar ion irradiated Co/Pt bilayer samples at different temperatures and fluences. They observe irradiation induced formation of stable Co–Pt phases, which appears to be more prominent at higher irradiation temperatures. A large shape anisotropy in the hysteresis loop is also observed when irradiated at higher temperatures, which could be indicative of a magnetization reversal. A CoPt ordered/disordered phase formation leads to the enhancement in the coercivity. The sequence of phase formations is predicted by the heat of formation rule. [ABSTRACT FROM AUTHOR]