Amorphisation and Recrystallisation of Nanometre Sized Zones in Silicon

Abstract

In this paper we present a detailed study in which the formation, by heavy ion impact, and thermal recrystallisation of individual amorphous zones have been studied using in-situ transmission electron microscopy. In agreement with previous work, we observe a reduction in the total volume of amorphous material contained within the amorphous zones following thermal annealing over a wide range of temperatures. When the evolution of the individual amorphous zones is followed, those with similar starting sizes are observed to recrystallise over a range of temperatures from 70 °C to 500 °C. The temperature at which an amorphous zone fully recrystallises does not appear to be correlated with initial size. In addition, zones are occasionally observed to increase in size temporarily on some isochronal annealing steps. Furthermore, observations during a ramp anneal show that many zones recrystallise in a stepwise manner separated by periods of stability. These phenomenon are discussed in terms of the I-V pair.