4.5.1 Damage Accumulation of Several Ion Implantation Steps

Since ion channeling significantly increases the depth of the doping profile several precautions are taken to reduce ion channelling in the actual fabrication processes. One of these methods is to convert parts of the silicon substrate to the amorphous state by ion implantation in advance to the implantation of the dopant species. For this method two ion implantations have to be performed immediately one after the other, without an annealing step in between. Then damage generated by the first ion implantation still exists at the beginning of the second implantation step.

Such a damage accumulation over several implantation steps can be handled. After each implantation simulation the complete damage information is stored in a file . Starting a new implantation step this file can be used to set an initial damage distribution .

Footnotes

... file

The name of the damage file is ACC_DAMAGE.DAT. It is located in the current working directory.

... distribution

The command-line parameter damageInput determines whether a previously generated damage file is considered.