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Research was conducted to study the n-p junction and material features of N-, P-, and N/P-implanted SiC epitaxial layers. A thick Sio2 passivation layer was deposited into the diode while contact holes were opened on the implanted n side. Results showed good lattice perfection in the material. They also indicated that the spectra on RT P-implanted material before annealing coincided with that of random spectra, suggesting amorphization of the material.

A study was conducted on nitrogen and aluminum implantations into undoped high-resistance and vanadium doped semi-insulating bulk 6H-SiC. The N and Al implants were conducted at 700 degrees C and 800 degrees C, respectively. The results indicate that the activations for both N and Al implants in bulk semi-insulating V-doped SiC were lower than the values in epitaxial layers. Moreover, the N implants exhibited thermal stability while the Al implants formed a shoulder in the implant tail region during annealing.

Al and B implantations into n type 3C-SiC and 6H at room temperature and 850 degrees Celsius are performed by annealing the samples at 1100 to 1400 degrees Celsius for 10 minutes. The Al implantation results in the occurrence of P-type conduction. The B type implantation yielded N-type conduction in the samples. An increase in the annealing temperature resulted in the gettering of the sample causing severe lattice damage.

The hydrological consequences of historical, contemporary and future human activities on a coastal system were investigated by means of numerical models. The changes in the morphology of the Lagoon of Venice during the last century result from the sedimentological response to the combined effects of human interventions on the environment and global changes. This study focuses on changes from 1927 to 2012 and includes the changes planned for the protection of the city of Venice from storm surges and exceptional tides under future sea level rise scenarios. The application of a hydrodynamic model to simulate the circulation of water masses and the transport of a passive tracer enabled the analysis of the morphodynamic effects on the lagoon circulation and the interaction with the sea. The absolute values of the exchange between the lagoon and sea increased from 1927 to 2002 (from 3900 to 4600m³ s-1), while the daily fraction of lagoon water volume exchanged decreased. At the same time, the water renewal time shortened from 11.9 to 10.8 days. Morphological changes during the last decade induced an increase of the basin-wide water renewal time (from 10.8 to 11.3 days). In the future, Venice Lagoon will evolve to a more restricted environment due to sea level rise and periodical closure of the lagoon from the sea during flooding events. Simulated scenarios of sea level rise showed that under fall-winter conditions the water renewal time will increased considerably especially in the central part of the lagoon. Furthermore, some considerations on the impact of the hydromorphological changes on the ecological dynamics are proposed. [ABSTRACT FROM AUTHOR]