Ion implantation is one of the key technologies for the fabrication of HgCdTe (MCT) infrared photodiodes. In order to achieve p-on-n type photodiode structure with better performance, the group V elements typically serve as p-type dopants, especially arsenic. In this chapter, ion profiles, defect microstructures, and surface amorphization of implanted group V dopants represented by arsenic into MCT epilayers were characterized by secondary ion mass spectroscopy (SIMS), transmission electron microscopy (TEM), and X-ray diffraction (XRD), respectively. The influences of some significant technological parameters related to ion implantation, such as implant energy, implant dose, ion beam current, barrier layer structure, on the distributions of ions and induced damages are analyzed. In addition, the high-temperature annealing used to eliminate induced damages and activate the electrical activity of ions was subjected to the as-implanted samples, and the ion diffusion profiles and surface microstructures were acquired and analyzed. Finally, the computer simulations on the collision of incident ions and lattice atoms were carried out to study the distributions of ions and recoil atoms numerically. The simulation results are in good agreement with the experimental data.
Part of the book: Ion Beam Applications