Scanning probe microscopy of single Au ion implants in Si
2006 (English)In: Materials science & engineering. C, biomimetic materials, sensors and systems, ISSN 0928-4931, Vol. 26, no 07-maj, 782-787 p.Article in journal (Refereed) Published
We have studied 5 MeV Au2+ ion implantation with fluences between 7 x 10(7) and 2 x 10(8) cm(-2) in Si by deep level transient spectroscopy (DLTS) and scanning capacitance microscopy (SCM). The DLTS measurements show formation of electrically active defects such as the two negative charge states of the divacancy (V-2(=/-) and V-2(-/0)) and the vacancy-oxygen (VO) center. It is observed that the intensity of the V-2(=/-) peak is lower compared to that of V-2(-/0) by a factor of 5. This has been attributed to a highly localized distribution of the defects along the ion tracks, which results in trapping of the carriers at V-2(-/0) and incomplete occupancy of V-2(=/-). The SCM measurements obtained in a plan view show a random pattern of regions with a reduced SCM signal for the samples implanted with fluence above 2 x 10(8) cm(-2). The reduced SCM signal is attributed to extra charges associated with acceptor states, such as V-2(-/0), formed along the ion tracks in the bulk Si. Indeed, the electron emission rate from the V-2(-/0) state is in the range of 10 kHz at room temperature, which is well below the probing frequency of the SCM measurements, resulting in freezing of electrons at V-2(-/0).
Place, publisher, year, edition, pages
2006. Vol. 26, no 07-maj, 782-787 p.
scanning probe microscopy, ion impact, DLTS, transient spectroscopy, irradiated silicon, divacancy, defects, traps
IdentifiersURN: urn:nbn:se:kth:diva-15766DOI: 10.1016/j.msec.2005.09.079ISI: 000238474700011ScopusID: 2-s2.0-33646847887OAI: oai:DiVA.org:kth-15766DiVA: diva2:333808
QC 20100525 QC 201109272010-08-052010-08-052011-09-27Bibliographically approved