Residual lattice damage in As-implanted and annealed Si

Residual damage in Si was examined by TEM after shallow As+ implantations (40 to 150 keV) and annealing in the temperature range of 800 to 10000C. After annealing at 8000C the damage consists of many small interstitial-type prismatic dislocation loops. The structures obtained after annealing at higher temperatures are different for implantations into Si covered with a thin (100 to 200 A) layer of SiO2 and for implantations of large prismatic dislocation loops and half-loops intercepted by the Si surface, whereas implantation through oxide results in a layer of irregularly shaped dislocation loops which is not connected to the surface. The development of these structures is discussed as arising from the healing of ion-bombardment damage and the diffusion of As into deeper regions of Si and from an influence of recoiled O atoms for implantations through SiO2 layers