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We report the activation of silicon implanted with phosphorus and boron atoms by infrared semiconductor laser annealing using carbon films as an optical absorption layer. 2-mm surface region was heated above 1000 C longer than 22 ms by scanning the laser beam for a dwell time of 40 ms. We carried out implantations of 1 Â 10 15 cm À2 phosphorus atoms at 100, 300, and 500 keV, and boron clusters with a boron concentration of 1 Â 10 15 cm À2 at 6 keV. Laser irradiation at 375 kW/cm 2 was conducted to activate impurities. Secondary ion mass spectrometry measurement revealed that laser annealing caused no substantial change in the phosphorus and boron atom profiles. Laser-induced recrystallization of surface amorphized regions caused by the ion implantation was analyzed using the optical reflectivity spectra ranging from 250 to 1000 nm. The free carrier absorption analyses indicated that the phosphorus and boron atoms were effectively activated by laser annealing.

We have measured absolute cross sections of multiple ionization in coincidence with final charge states of projectiles for collisions of C3+ ions with Ar atoms at 2 MeV. At this collision energy, the recoil ions with low charge states were mainly produced by pure ionization while capture and loss ionization were important processes for the production of recoil ions with higher charge states. In an analysis of the data, an independent-electron model was applied. The results indicate that the ionization probability of the target electron depends on the impact parameter in ionization processes, such as pure-, capture-, and loss-ionization. The obtained values were compared with calculations by a classical-trajectory Monte Carlo (nCTMC). The experimental cross sections are in good agreement with the calculated values for pure, single-capture and single-loss ionization.

Newly developed sweep beam Cluster ion implanter: CLARIS with 0.2-7keV energy range for Boron beam and 1-10keV energy range for Carbon beam is introduced. Novel Cluster ion implantation technology is capable for 45nm beyond device requiring USJ formation (<15nm) with high retain dose (>70%) and low sheet resistivity (<1200Ω/sq). Comparison of retain dose and sheet resistivity of B 18 , BF 2 , and B beams with FLA shows the superiority of the B18 implantation for less than 500eV implantation.

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