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M Alatalo

Publications and source records attributed to M Alatalo.

13 recordsLinked to original sources
PubMed2003

Vacancy defects as compensating centers in Mg-doped GaN.

We apply positron annihilation spectroscopy to identify V(N)-Mg(Ga) complexes as native defects in Mg-doped GaN. These defects dissociate in postgrowth annealings at 500-800 degrees C. We conclude that V(N)-Mg(Ga) complexes contribute to the electrical compensation of Mg as well as the activation of p-type conductivity in the annealing. The observation of V(N)-Mg(Ga) complexes confirms that vacancy defects in either the N or Ga sublattice are abundant in GaN at any position of the Fermi level during growth, as predicted previously by theoretical calculations.

Journal Article↗
PubMed1989

Replication error, a new hypothesis to explain the origin of a supernumerary marker chromosome in a mentally retarded boy.

A marker chromosome present in all the lymphocytes of a mentally retarded boy (47,XY,+mar) was identified. The karyotype of all fibroblasts was normal, 46,XY. His parents had normal karyotypes. The supernumerary marker chromosome was interpreted as a dicentric palindromic chromosome iso(9) (pter----q12, q12----pter). The marker chromosome may have originated through a ligation error in a replication fork during the S-phase followed by a new replication (endoreduplication).

Child, Preschool↗