Undoped LPCVD silicon films have been deposited at five temperatures between 560° and 620°C. The films were characterized as grown and after thermal annealing at 900°, 950°, and 1000°C. We used x‐ray diffraction, TEM, SEM, Raman and elastic light scattering, optical absorption and reflection, and other techniques in order to obtain information on the grain size, structure, structural perfection, and surface roughness. We found that polysilicon films of good structural perfection, low strain, and small surface roughness are obtained when the films are deposited in the amorphous phase and subsequently crystallized at 900°–1000°C. Such films are superior in all investigated material aspects to films grown in the crystalline phase.

Undoped and in situ phosphorus-doped low pressure chemical vapor deposited polysilicon films have been studied by various structural analysis and optical techniques as a function of deposition temperature. Polysilicon films of high quality can only be obtained by deposition in the amorphous phase and subsequent crystallization.

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In this paper experiments 011 photoluminescence (emission and excitation spectra) of CdIn,S, crystals and of mixed crystals with In$, a t 77 "Ti are reported. The results are interpreted on the basis of the partial inversion of the thiospinel CdIn,S,. I n CdIn,S, the two emission bands observed in the red spectral region are ascribed to a Cd ion at an octahedral site and an I n ion a t a tetrahedral site. This model describes the intensity and wavelength variation of the photoluminescence of the mixed crystal system CdIn,S,/In,S, surprisingly well. Evidence is given that the energy gap in all these crystals is indirect. I n an appendix some etching procedures are listed.I n dieser Arbeit wird iiber Photolumineszenz-Experimrnte (Emissionsund Anregnngsspektren) an CdIn,S,-Kristallen und an Mischkristallen niit Tn,S, berichtet. Die Messungen wurden bei 77 O K ausgefuhrt. Die Resultate werden arif Grund der teilweisen Inversion des Spinelgitters von CdIn,S, erklart. I m roten Spektralbereich werden zwei Emissionsbanden beobachtet, die je einem Cd-Ion auf Oktaederplatz und einem In-Ion auf Tetraederplatz zugeordnet werden konnen. &fit diesem Model1 laSt sich sowohl die Intensitkt als auch die Wellenlangenabhangigkeit der Photolumineszenz im Mischkristallsystem CdIn,S,/ In,S, iiberraschend gut beschreiben. Ferner werden Hinweise diskutiert, die vermuten lassen, daB der Band-Band-ubergang in allen untersucliten Kristallen indirekt ist. I m Anhang sind einige Atzvorschriften zusammengestellt.