Primary processes of damage formation in semiconductors

Abstract

In this chapter damage formation and amorphisation in various semi-conductors are reviewed with special focus on primary processes. Trends are shown how the parameters during ion implantation influence damage formation and to what extend the results for the various semiconductors can be generalised. It is shown that three groups of semiconductors can be identified. One group of materials exhibits a continuous transition towards amorphisation at sufficiently low temperatures. In these materials comparable mechanisms of defect formation are observed provided the implantation temperature is similarly close to or below the corresponding critical temperature of amorphisation, Tc, the concept of which is discussed in this chapter. In a second group, amorphisation can be achieved at low temperatures only and only by secondary processes resulting in a discontinuous transition to amorphisation. And in a third group of materials amorphisation by ion implantation is not observed even not at low temperatures for moderate ion fluences which do not significantly alter the stoichiometry of the material. Various models are applied for describing the damage evolution. This represents a further step towards a prediction of damage to be expected for certain irradiation conditions in the corresponding materials.