Direct implantation of dopant ions is the most precise method for obtaining a desired dopant profile in a semiconductor substrate. However, in order to achieve satisfactory electrical properties, lattice defects introduced by the energetic dopant ions and by the subsequent annealing process must be confined or eliminated. Because of the many parameters which can be varied during implantation and annealing, it is not generally feasible to survey all conditions. Consequently, the most efficient approach is to understand the mechanisms of defect formation and annealing so that guidelines for choosing a set of implantation/annealing conditions can be determined.Since implantation depths are usually much less than one micron, suitable defect characterization techniques must demonstrate high spatial resolution. Cross-sectional transmission electron microscopy (XTEM) is one such technique. With a resolution (lateral and depth) of ∼0.2nm, the atomic structure of implantation-related defects is accessible.
