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Unseeded and seeded crystallization of thick polycrystalline silicon (up to 10 μm) on SiO2 is carried out in a zone melting process using irradiation with a halogen lamp working in the scanning mode. Recrystallization without crystallization seed results in large monocrystalline areas (up to several millimeters wide and about 10 mm long). The seeded solidification produces monocrystalline silicon (100) oriented. The results indicate as well the influence of thermal conditions and impurity distribution as the interface kinetics on the feature and crystalline quality of the recrystallized film.

In strained Sia−xGex heterojunction internal photoemission (HIP) photodiodes the spectral response can be tailored over a wide wavelength range by varying the Ge content. In this paper heavily in situ boron doped SiGe layers with 30% Ge were grown by low pressure rapid thermal chemical vapour deposition (LP(RT)CVD). The detectors exhibit a cut-off wavelength of 8.5 μm. A delta-like P peak, incorporated by atomic layer deposition technique, shifts the cut-off to shorter wavelengths. This shift is related to an increase of the barrier height at the SiGe/Si interface caused by the narrow n+-doped layer in agreement with device simulation. In this way the trade off between critical film thickness for high Ge content film growth and absorption depth for proper detector response can be overcome.

Thick SOI layers obtained by zone melting with and without seeds, respectively, have been investigated by EBIC with respect to their electrical properties (electrical homogeneity, electrically active defects, minority-carrier diffusion length). A variety of inhomogeneities being partly of complex origin has been observed. Their formation is affected by existence of seeds. Besides usual dark contrasts due to defects acting as recombination site there is evidence that some contrast phenomena are caused by dopant inhomogeneities

Seeded recrystallization of thick (up to 25 pm) polycrystalline silicon on SiO, using zone melting technique provides films which contain no grain boundaries and exhibit large areas without subgrain boundaries (mm,). The results, especially the comparison of the two irradiation systems used (laser and strip heater), indicate the dominating role of the thermal gradient a t the crystallization front for the origin and arrangement of defects. The electrical properties measured a t CMOS transistors and diodes are comparable to a bulk reference preparation.Die Rekristallisation von dickem, polykristallinem Silizium auf SiO, in einem Zonenschmelzprozell fuhrt bei Verwendung eines Kristallisrttionskeimes zu Schichten, die keine Krongrenzen enthalten und ausgedehnte Gebiete ohne Kleinwinkelkorngrenzen aufweisen (mme). Die dargestellten Ergebnisse, besonders der Vergleich der Bestrahlung mit Laser und Streifenheizer, zeigen den dominierenden EinfluB des Temperaturgradienten an der Kristallisationsfront auf die Entstehung und Anordnung der Defekte. CMOS-Tramistoren und Dioden, erzeugt in den SOI-Schichten, haben mit in einkristallinen Substraten priiparierten Strukturen vergleichbare Eigenschaften.