Observation of the triplet metastable state of shallow donor pairs in AlN crystals with a negative-U behavior: a high-frequency EPR and ENDOR Study.
Theoretical predictions about the n-type conductivity in nitride semiconductors are discussed in the light of results of a high-frequency EPR an ENDOR study. It is shown that two types of effective-mass-like, shallow donors with a delocalized wave function exist in unintentionally doped AlN. The experiments demonstrate how the transformation from a shallow donor to a deep (DX) center takes place and how the deep DX center can be reconverted into a shallow donor forming a spin triplet and singlet states.
Orlinskii
Sergei B
SB
Huygens Laboratory, Leiden University, P.O. Box 9504 2300 RA Leiden, The Netherlands.
Schmidt
Jan
J
Baranov
Pavel G
PG
Bickermann
Matthias
M
Epelbaum
Boris M
BM
Winnacker
Albrecht
A