摘要 |
In ion implantation processes for forming junctions in semiconductor devices, a proportion of ions implant into the semiconductor material beyond the desired junction depth due to channelling along axes and planes of symmetry in the crystal. A method is provided in which ions are implanted at a series of different energies starting with a lower energy than that required for the desired junction depth. The initial amorphising of the surface regions of the semiconductor during the lower energy implantation reduces the channelling probability when the ions are subsequently implanted at the full energy resulting in a more sharply defined junction.
|