Defects in Ge caused by sub-amorphizing self-implantation: Formation and dissolution

High Resolution X-Ray Diffraction (HRXRD) was used to study the strain evolution of lattice defects formed in an array of B delta layers grown by Molecular Beam Epitaxy (MBE) and damaged by sub-amorphizing Ge self-implantation The MBE structure was implanted at room temperature (RT) with 840 keV Ge at a dose of 15 x 10(12) Ge/cm(2) First of all, we observed a RT strain reduction of similar to 40% with respect to the strain value found in the just-implanted sample This strain ageing phenomenon saturates in about 5 months Then, the complete defects dissolution was monitored by in-situ HRXRD during isochronal annealings. Three others strain-recovery steps were identified. the last at T=157 degrees C Moreover, Secondary Ion Mass Spectrometry performed after the strain recovery did not detect any B diffusion till T was raised up to 840 degrees C, measuring in this case a B diffusion equal to the equilibrium one. The whole set of data will be discussed and compared with existing literature (C) 2009 Elsevier B.V. All rights reserved.