G. Mattei et Am. Mazzone, ANALYSIS OF IRRADIATED AG AND SI BY MOLECULAR-DYNAMICS AND SIMULATED HREM IMAGES, Ultramicroscopy, 58(3-4), 1995, pp. 223-231
In order to clarify the limits of HREM observations of defects due to
radiation damage, a simulation method has been designed which combines
molecular dynamics and HREM simulation. Disorder due to ion irradiati
on in Si and Ag is simulated by using a molecular dynamics technique a
nd HREM images are computed by a multislice dynamic procedure. The con
ditions to achieve a goad HREM visibility of such defective structures
have been investigated by analyzing the effects of the physical input
s of molecular dynamics as well as the ones of the instrumental parame
ters of TEM observations. This analysis indicates that the structure o
f the damaged region is not critical. On the contrary, the fractional
disorder is of paramount importance and determines the conditions lead
ing to an appreciable contrast of the disordered region against the cr
ystalline background.