Transient enhanced diffusion after laser thermal processing of ion implanted silicon

The effect of laser thermal processing (LTP) on implantation-induced defect evolution and transient enhanced diffusion (TED) of boron was investigated . A 270-Angstrom-thick amorphous layer formed by 10 keV Si+ implantation wa s melted and regrown using a 20 ns ultraviolet laser pulse. Transmission el ectron microscopy revealed that recrystallization of the amorphous layer fo llowing LTP results in a high concentration of stacking faults and microtwi ns in the regrown region. Also, the end-of-range loop evolution during subs equent 750 degrees C furnace annealing, is different in a LTP sample compar ed to a control sample. Secondary ion mass spectroscopy of a boron marker l ayer 6000 Angstrom below the surface showed that LTP alone produced no enha nced diffusion. However, during subsequent furnace annealing, the boron lay er in the LTP sample experienced just as much TED as in the control sample which was only implanted and furnace annealed. These results imply that las er melting and recrystallization of an implantation-induced amorphous layer does not measurably reduce the excess interstitials released from the end- of-range implant damage. (C) 1999 American Institute of Physics. [S0003-695 1(99)00149-7].