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Implantation of molecular ions of decaborane (B[sub 10]H[sub 14]) is an alternative path to ultra shallow doping of Si with B ions of very low energy (< 1 keV). Because of their mass, the molecular ions with an energy an order of magnitude larger than an energy of B[sup +] monomer ions achieve the same implantation depth. In addition, the molecular ions transport ten times more B per unit charge. To assess the feasibility of this approach, the properties of the decaborane ion beams with energies from 2 to 10 keV were examined. The ions were generated in an electron impact ionization source and transported to a sample chamber through a 2.5 m long beam line with an analyzing magnet. Experiments with electrostatic beam deflection show that the large ions survive the transport in the implanter environment and that neutralization is negligible. Si samples were implanted with decaborane ions and the implanted dose measured by current integration was compared with the amount of retained [sup 11]B obtained by nuclear reaction analysis. The retained dose was found to be larger for decaborane ions, which may be attributed to a sputtering yield of Si, smaller than for low energy B[sup +] ions. Development of ion sources capable of generating decaborane ion beams has reached the stage where batches of wafers can be implanted. The implanted B profiles and electrical characteristics of test MOS transistors fabricated using implantation with decaborane ions and B[sup +] and BF[sub 2][sup +] ions of equivalent energy were found to be very similar. The results confirm the potential of decaborane ion beams as an alternative technology for manufacturing of ultra shallow p-type junctions in Si. More research is needed to fully understand the effects of cluster ions in semiconductors. [ABSTRACT FROM AUTHOR]