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High energy ion backscattering has been used to study the surface chemistry of the sensitization false(SnCl2false) and activation false(PdCl2false) processes used to prepare nonconductive substrates for electroless plating. This method of surface preparation is compared to catalysis using mixed Pd‐Sn colloidal solutions. While the redox reaction between divalent Sn and Pd may occur during the activation of sensitized surfaces, it is suggested that any zero‐valent Pd so produced only becomes catalytically active after a significant (∼100 sec) immersion time in the electroless plating solution.

An experimental study has been made of the anodic dissolution of silicon in aqueous HF solution with emphasis on heavily doped n‐type. Current‐voltage curves, the effective dissolution valence, and the critical current density have been determined for n, n+, and p samples. Since n+ silicon has a resistivity less than 0.05 ohm‐cm, it can be electropolished while higher resistivity material exhibits a current saturation effect although breakdown occurs at only a few volts. Minority carrier generation within the space charge region does not account for the magnitude of the saturation current for n‐type and extensive attack was evident at the surface of n‐type which had received prolonged anodic treatment. The critical current density for n+ samples was found to be a function of the resistivity.

Comparative annealing studies were carried out upon Si layers implanted with Ne+, Ar+, and Kr+ ions. Ion doses were in the range 6×1014/cm2–6×1015/cm2, and ion energies were chosen so that the matrix damage had approximately the same depth for each ion type. Annealing was carried out in a N2/dilute O2 ambient or in vacuum at 600, 900, or 1100 °C. Implanted layer structures were studied using electron-microscope and ion-backscattering techniques. The orientation of the Si substrate and ion-beam heating effects were found to be important in determining layer-annealing behavior. The latter depended weakly, if at all, upon the nature of the annealing ambient. Layer recrystallization was studied as a function of implanted ion type and dose, and the effects of inert gases trapped in the Si lattice were examined. The suitability of implantations for device gettering applications were considered. Crystallographic defects produced by annealing ranged from polycrystals and microtwins to simple dislocation networks. Faceted gas bubbles invariably occurred in annealed layers, and their geometry gave information regarding low-energy planes in Si. Electron diffraction and He+-ion channeling effects produced by twins in recrystallized layers have also been examined.