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Results show that the phase formation in the implantation process of aluminum into silicon carbide occurs at an aluminum concentration above 10 at. %. Data reveal that phase transformation changes the material properties of the alumina/silicon carbide system.

The influence of high dose ion irradiation through amorphous surface layers in single crystalline 6H-SiC at elevated temperatures was analyzed. Quantification for irradiation at 500 degrees Celsius was conduced on material swelling, subsequent densification and surface erosion. Ion beam induced recrystallization was examined in the temperature range from 300-1300 degrees Celsius. The findings indicate that perfect epitaxial regrowth in (0001)-oriented 6H-SiC cannot be achieved by ion irradiation at elevated temperatures.

Step height measurements, optical microscopy and x-ray diffraction analysis were use to systematically examine the annealing behavior of amorphous silicon carbide (SiC) layers created by the implantation of Si MeV into 6H-SiC. The findings revealed two annealing stages. The first stage is between 200 degrees and 700 degrees centigrade, at which period the amorphous layer densificates after five minutes. The second stage is at temperatures beyond 700 degrees centigrade and is characterized by the combined defect annealing and recrystallization.

The ion fluence and temperature dependence of the amorphization process in silicon carbide induced by irradiation has been investigated using in situ laser reflectometry and ex situ Rutherford backscattering spectrometry. The amorphization fluence relies weakly on temperature below 300 K, and strongly above 300 K. A higher ion fluence for the amorphization of silicon carbide is needed at very low temperatures compared to silicon.

A study was conducted on the kinetics of ion-beam-induced interfacial amorphization (IBIIA) in silicon. This process is different from bulk amorphization in terms of the critical energy density approach and the evolution of the roughness of the amorphous/crystalline interface during ion irradiation. The findings indicate that the temperature dependence of IBIIA can be characterized by three regimes: athermal ion-beam-induced defect generation, thermally activated recombination of defects and athermal transport of defects towards the amorphous/crystalline interface.

Heavily p-type doped Ge layers are prepared by 100 keV Ga implantation and subsequent flash lamp annealing and the structure of the doped layer and the Ga distribution are examined by Rutherford backscattering spectrometry. The Ga activation is correlated with the layer regrowth and incomplete epitaxial regrowth has led to lower activation.

The electrical properties of heavily Al doped single and nanocrystalline 4H-SiC layers on semi-insulating 4H-SiC substrate, prepared by multienergy, high-fluence Al implantation and subsequent furnace annealing, are examined by sheet resistance and Hall effect measurements. In single crystalline material efficient impurity band conduction due to strongly interacting acceptors can be achieved in the range of supersaturation and for lower doping levels impurity band conduction is more effective in nanocrystalline SiC.

The effect of implantation temperature on the structural properties of diamond implanted with high fluences of Si between 5.3 x 10(sub 17) Si cm(sub -2) and 1 x 10(sub 18) Si cm(sub -2) was investigated. X-ray diffraction revealed the formation of cubic SiC nanocrystallites in a buried layer inside the implanted diamond.

High-fluence Si implantation into natural diamond at elevated temperatures between 760 and 1100 degree-Celsius is used to fabricate the epitaxial SiC nanocrystals. The results reveal a high, thermally stable n-type conductivity with electron concentrations exceeding 10(super 20) cm(super -3) and mobilities higher than 2 square-cm/V s.

Al supersaturated SiC layers were produced by multienergy, high-dose ion implantation into 6H- and 4H-SiC. In dependence on the implantation conditions damaged single-crystalline, amorphous, or nanocrystalline layers were formed.

The sheet resistance and structural properties of high-fluence Si-implanted diamond are investigated. High temperature implantation of Si into diamonds has shown to lead to the formation of 3C-SiC nanocrystals in a buried layer.

Step height measurements, optical microscopy and x-ray diffraction analysis were use to systematically examine the annealing behavior of amorphous silicon carbide (SiC) layers created by the implantation of Si MeV into 6H-SiC. The findings revealed two annealing stages. The first stage is between 200 degrees and 700 degrees centigrade, at which period the amorphous layer densificates after five minutes. The second stage is at temperatures beyond 700 degrees centigrade and is characterized by the combined defect annealing and recrystallization.

The results of epitaxial crystallization of Si by mega-electron-volt heavy-ion-beam irradiation can be understood based on the 'point defect diffusion model.' The inelastic electronic scattering effects need not be determined in explaining the decrease in the normalized crystallization rate with increasing nuclear deposited energy.