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Aluminum oxide films deposited onto silicon substrates by hydrolysis of AlCl3 show marked differences in etch rates, electron diffraction patterns, ir absorption spectra, and chlorine contents between films grown below 700°C and above 800°C. Analysis of the composition from the yield of backscattered MeV He ions indicated that both film types were stoichiometric throughout the layer thickness. These analyses indicated that the Cl was incorporated uniformly in the low-temperature-deposited films to a level of about 2 at. %.

Diffusion of Al into a polycrystalline Si layer chemically deposited at 640 °C was studied by capacitance-voltage characteristics, sheet resistance, and electron microprobe measurements in the 180–550 °C temperature range. It has been found that diffusion of Al into polycrystalline Si takes place at temperatures as low as 300 °C, and that the polycrystalline Si becomes electrically conductive. The sheet resistance of polycrystalline Si decreases with increasing annealing temperature. Annealing at a higher temperature, however, induces migration and recrystallization of Si in Al, and the original polycrystalline-Si layer loses its integrity.

Single-step and double-step annealing behavior of highly p+ -ion-implanted layers was investigated by means of four-point probe measurements, x-ray double-crystal spectrometry, and electron diffraction patterns. The x-ray double-crystal spectrometry data indicated that, in the case of single-step annealing, the layer implanted with doses lower than 3 X 10 15 /cm' ions was recovered with the increase of annealing temperature, while the sample implanted with doses of 1 X 10 16 /cm' ions showed the opposite behavior. That is, the latter sample showed a very poorly recrystallized layer with poly crystalline regions when it was annealed at temperatures higher than 1000 'C. However, in the case of double-step annealing, the highertemperature annealing process, conducted after long 560'C annealing, made it possible to obtain a good recrystallized layer, compared with the single-step annealing case. These results were confirmed by electron diffraction patterns.