Experimental confirmation of the predicted shallow donor hydrogen state in zinc oxide.
We confirm the recent prediction that interstitial protium may act as a shallow donor in zinc oxide, by direct spectroscopic observation of its muonium counterpart. On implantation into ZnO, positive muons--chemically analogous to protons in this context--form paramagnetic centers below about 40 K. The muon-electron contact hyperfine interaction, as well as the temperature and activation energy for ionization, imply a shallow level. Similar results for the cadmium chalcogenides suggest that such shallow donor states are generic to the II-VI compounds. The donor level depths should serve as a guide for the electrical activity of interstitial hydrogen.
Cox
S F
SF
ISIS Facility, Rutherford Appleton Laboratory, Chilton OX11 0QX, UK.
Davis
E A
EA
Cottrell
S P
SP
King
P J
PJ
Lord
J S
JS
Gil
J M
JM
Alberto
H V
HV
Vilão
R C
RC
Piroto Duarte
J
J
Ayres de Campos
N
N
Weidinger
A
A
Lichti
R L
RL
Irvine
S J
SJ