In this work we study the optimization of laser-fired contact (LFC) processing parameters, namely laser power and number of pulses, based on the electrical resistance measurement of an aluminum single LFC point. LFC process has been made through four passivation layers that are typically used in c-Si and mc-Si solar cell fabrication: thermally grown silicon oxide (Si0 2 ), deposited phosphorus-doped amorphous silicon carbide (a-SiC/H(«)), aluminum oxide (A1 2 0 3 ) and silicon nitride (SiN^/H) films. Values for the LFC resistance normalized by the laser spot area in the range of 0.65-3 mil cm 2 have been obtained.

Hyperdoped and textured silicon created with a femtosecond laser in the presence of SF 6 gas has a highly absorbing surface with extended spectral sensitivity in the infrared. The main drawback of this micro-and nanostructured material for photovoltaic (PV) cells is an increase in charge-carrier recombination at the surface due to the typically poor crystallinity of the surface layer. Laser annealing postprocessing of the black silicon (b-Si) surface is used to greatly reduce the crystal structure defects while maintaining sub-bandgap absorption. The back side of the cell is functionalized with spin-on doping and laser fired contacts to make an interdigitated back-contact proof-of-concept b-Si solar cell. It is shown that this cell has measurable PV efficiency in the sub-bandgap infrared, a promising step toward developing intermediate-band silicon PVs.

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An alternative method to generate chirp signals in SFCW-radars based on sigmadelta fractional synthesizers which allow to get high resolutions in a great bandwidth and with high linearity, necessary qualities for the systems SFCW.