ABSTRACTCross section TEM and channeling analysis show that the heating rate (HR) of a rapid thermal annealing (RTA) cycle affects the residual defect distribution in Si implanted with As⁺ to a heavy dose (≈ 10¹⁶ cm⁻²). Two defect bands are observed after solid phase epitaxial growth (SPEG): the first one centered at a depth corresponding to the projected range of the As (band I), and the second one located at depth corresponding to the original amorphous crystalline (a-c) interface (band II). The density of defects in band I is found to increase with the As dose, and with the annealing temperature (550 - 650°C, furnace annealing). However, for RTA (800 - 1000°C) both the density and depth distribution of these defects are dependent on HR. We propose that Si self-interstitials (Si_I) are created at the a-c interface when As becomes substitutional during SPEG. The SPEG velocity determines whether the Si_I are accommodated in the amorphous Si layer (low velocities) or are captured by the regrowing c-Si (high velocities)