Modification changes the properties of a material. Modification techniques include physical processes like heating, cooling, ion bombardment and injection, and chemical treatments. These processes can influence the flow of electrons in a material as well as improve performance and power.
Ion implantation, also called doping, uses high-energy injection to introduce precise amounts of a target material into a host to modify electrical or material properties. For example, implantation of boron and arsenic into silicon will increase conductivity and enable the creation of transistors and other devices. The injection into silicon of other species such as hydrogen or fluorine results in defect trap passivation and reduced leakage current. Implants can also be used to modify film properties to increase etch rates and alter dielectric constants.
Annealing heats targeted regions of silicon and has the ability not only to restore the host material’s lattice following implantation but also to modify the material through exposure to select chemistry while heating. Plasma nitridation can embed a precise amount of nitrogen, oxygen, or other species that can modify the dielectric constant of films to suit the needs of a particular device.