title: Structure and low-temperature thermal relaxation of ion-implanted germanium.
abstract: The structure of implantation-induced damage in Ge has been investigated using high resolution extended X-ray absorption fine structure spectroscopy (EXAFS). EXAFS data analysis was performed with the Cumulant Method. For the crystalline-to-amorphous transformation, a progressive increase in bond-length was observed without the presence of an asymmetry in interatomic distance distribution (RDF). Beyond the amorphization threshold the RDF was dose dependent and asymmetric, where the bond-length and asymmetry increased as functions of ion dose. Such an effect was attributed to the formation of three- and five-fold coordinated atoms within the amorphous phase. Low-temperature thermal annealing resulted in structural relaxation of the amorphous phase as evidenced by a reduction in the centroid, asymmetry and width of the RDF, as consistent with a reduction in the fraction of non four-fold coordinated atoms. The results have been compared to other EXAFS studies of amorphous Ge, and it is suggested that the range of bond-lengths reported therein is related to the sample preparation method and state of relaxation.
authors.affiliation: Research School of Physical Sciences and Engineering, Australian National University, Canberra.
authors.forename: C J
authors.initials: CJ
authors.lastname: Glover
authors.forename: M C
authors.initials: MC
authors.lastname: Ridgway
authors.forename: K M
authors.initials: KM
authors.lastname: Yu
authors.forename: G J
authors.initials: GJ
authors.lastname: Foran
authors.forename: C
authors.initials: C
authors.lastname: Clerc
authors.forename: J L
authors.initials: JL
authors.lastname: Hansen
authors.forename: A
authors.initials: A
authors.lastname: Nylandsted-Larsen