A <100> Czochralski-grown wafer was implanted with 100keV Si+ to a sub-amorphizing dose of 2 x 1014/cm2. The annealing kinetics of extended defects in implanted material were investigated by means of in situ annealing in a transmission electron microscope. After annealing (300s, 800C), a dense collection of both {311} defects (3 x 1011/cm2) and small sub-threshold dislocation loops (1011/cm2) was observed. During further annealing, the {311} defect density decreased rapidly and the loop density increased. The evolution of some 500 {311} defects was monitored as a function of annealing time. The unfaulting of a {311} defect was observed to be the source of every sub-threshold loop which was observed to form; giving about 150 loops in the studied region. After initial annealing (300s, 800C), the probability of a {311} defect unfaulting into a loop was about 50%. It was concluded that unfaulting of the {311} defects was the source of sub-threshold dislocation loops in non-amorphized ion-implanted material. It was noted that 70% of the loops which formed had a Burgers vector of a/3<111>, while 30% were perfect; with a Burgers vector of a/2<110>.

{311} defects in silicon J.Li, K.S.Jones: Applied Physics Letters, 1998, 73[25], 3748-50