The effect of implantation, energy, and dose on extended defect formation for MeV phosphorus implanted silicon

The effect of dose and energy on postannealing defect formation, for high e nergy (MeV) phosphorus implanted into epitaxially grown silicon, has been s tudied by etch pits and transmission electron microscopy (TEM). The phospho rus dose was varied from 1x10(13) to 5x10(14) cm(-2) and the energy was var ied from 180 to 5000 keV. After implantation, the wafers were processed thr ough subsequent annealing cycles which simulates a typical advanced complem entary metal-oxide-semiconductor process to understand the formation of the defects in the near surface and projected range. For phosphorus energies a bove 500 keV, the threading dislocation density (TDD), increases dramatical ly with increasing dose from below the minimum detection limit (5x10(3) cm( -2)) at a dose of 1x10(13) cm(-2) to a maximum above 1x10(6) cm(-2) for a d ose of 1x10(14) cm(-2). However, with further increases in dose, the TDD de creases back close to the minimum detection limit. Plan-view TEM suggests t hat with increasing dose, the formation of extended defects at the projecte d range reduces the TDD. For a fixed dose of 1x10(14) cm(-2), the TDD exhib its a superlinear increase of nearly 3 orders of magnitude as the implant e nergy is increased from 180 to 2000 keV. With further increases in implant energy, the TDD saturates at a value around 2x10(6) cm(-2). The marked effe ct of dose and energy on the TDD can be partially understood from homogeneo us nucleation theory. (C) 1999 American Institute of Physics. [S0003-6951(9 9)05443-1].