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Epitaxial growth of SiC on α-SiC(0001) substrates was carried out at relatively low temperatures (900–1000°C) and high growth rates (about 1 nm/min), by means of solid-source molecular beam epitaxy controlled by a quadrupole mass spectrometry based flux meter. The films were obtained on silicon-stabilized surfaces showing (3 × 3) and (2 × 2) superstructures. The reflection high-energy electron diffraction (RHEED) and transmission electron microscopy (TEM) investigations show, independent of the surface orientation, that the film growth can be quantified in two steps: In the initial stage of growth, at first the Si-determined superstructure will be formed. Despite the low temperature, growth of SiC then proceeds in a layer-by-layer mode leading to flat film-substrate interfaces. This result demonstrates the significance of surface reconstruction for the growth process, corresponding to results recently obtained using gas source molecular beam epitaxy. The films grow by stacking of laminae of α-and β-SiC, respectively, which may be attributed to fluctuations in the Si adlayer thickness. Films grown on off-oriented substrates contain many defects, likely double-positioning boundaries, directly associated with surface steps. For increasing film thickness during the film growth this boundaries may be eliminated. Films grown on well-oriented substrates show only a few of these defects. In case of increasing Si excess flux during the growth, the TEM investigations, RHEED patterns and damped RHEED-oscillations indicate an abrupt change in the growth process. This is due to the formation of Si islands on the film surface and the SiC island growth by carbonization of these islands. Only β-SiC was found in this case.

During the etching of AZ 1350 photoresist in O2 and O2/CF4 discharges, ground-state concentrations of atoms (O, F, and H), and small radicals (OH, HO2, RO2) were measured in the discharge afterglow by EPR spectroscopy. In the case of CF4/O2 discharges, the dependence of O and F atom concentrations on the etch time reflects both surface oxidation and fluorination reactions in accordance with existing etch models. In the case of high-rate resist etching in pure O2 discharges, high concentrations of product radicals (H, OH and HO2) were detected and compared with resist free O2/H2O discharges. Kinetic modeling of the afterglow reactions reveals that the mean lifetime and, accordingly, the diffusion length of the etchant species O(3P) is drastically reduced in rapid reactions with OH and HO2. The results are used to simulate both etch homogeneity and the loading effect in a simple etch model.

Radiofrequency discharges in neat BCI3 exhibit 3 broad molecular emissions with intensity maxima at about 305, 350, and 480 nm. The 350 nm system consists of a progression of bands with an average separation of about 130 cm−1. All three emissions have an identical excitation kinetics in pulse discharges and are, therefore, believed to originate from the same emitter. Arguments are given that the emitter might be electronically excited BCl2. The dominant process of BCl(A) formation in neat BCl3 at low r.f. power is shown to be direct electron impact excitation of BCl(X). A transient excess population of BCl(A1II) in BCl3/Ar discharges is explained as due to an energy transfer from argon metastables.