Implantation of Si under extreme conditions: The effects of high temperature and dose on damage accumulation

The accumulation of lattice damage in Si(100) during ion irradiation at extreme dose and temperature was investigated. Irradiation above the ion-induced, crystal-to-amorphous transition temperature (similar to 200 degrees C) enabled damage growth to be studied to arbitrarily high dose. Electron microscopy and Rutherford backscattering spectrometry were used to characterize the growth of damage under these extreme conditions, as well as its microstructural evolution. These observations are correlated both to irradiation conditions and the effects of ion-solid chemistry associated with the use of atomic ions dissimilar to the bulk atoms. These chemical effects are isolated by comparing results for Si+- with P+-ion irradiations, and As+- with Ge+-irradiations. Each combination includes an isoelectric and dopant ion of nearly identical mass for separating out the effects of the ion-solid chemistry. A mechanism to account for the formation of the ion-induced morphology under extreme irradiation conditions is presented.