Hydrogen can have undesirable effects on the electrically active dopant profile in the near-surface region of semiconductors and thus influence the switching and transmission characteristics of devices. However, hydrogen is present in virtually every step during the processing of Si and III-V devices, forming passivating complexes with acceptors (bonding configuration, left) and donors (anti-bonding configuration, right). The inplantation, and diffusion of the hydrogen are followed using, for example, SIMS and infrared spectroscopy.