Effects of ion-beam mixing on the epitaxial growth of MoSi₂ on (111)Si

Both plan-view and cross-sectional transmission electron microscopy as well as sheet resistance measurement have been applied to study the effects of As⁺ ion-beam mixing on the epitaxial growth of MoSi₂ on (111)Si. Significant improvement in the epitaxial growth of MoSi₂ on (111)Si and lower electrical resistivity of the MoSi₂ overlayer were found as a result of ion-beam mixing. Island formation was almost completely alleviated in samples implanted under suitable conditions and subsequently annealed up to 1100 °C. The dispersion of impurities near the Mo/Si interface and/or the generation of defects as a result of the ion-beam mixing are thought to be particularly beneficial to the growth of MoSi₂ epitaxy on silicon. The ineffectiveness of the ion-beam mixing for the improvement of the silicon surface coverage in some instances is attributed to the more pronounced accumulation of As atoms at the MoSi₂/Si interface to increase the interface energy so that island formation becomes energetically more favorable.