Hydrogen: a relevant shallow donor in zinc oxide.
Electron paramagnetic resonance and Hall measurements show consistently the presence of two donors ( D1 and D2) in state-of-the-art, nominally undoped ZnO single crystals. Using electron nuclear double resonance it is found that D1 shows hyperfine interaction with more than 50 shells of surrounding 67Zn nuclei, proving that it is a shallow, effective-mass-like donor. In addition D1 exhibits a single interaction with a H nucleus ( a(H) = 1.4 MHz), thus H is the defining element. It is in agreement with the prediction of Van de Walle [Phys. Rev. Lett. 85, 1012 (2000)] that H acts as a donor in ZnO. The concentration of D1 is 6x10(16) cm(-3) emphasizing its relevance for carrier statistics and applications.
Hofmann
Detlev M
DM
I. Physikalisches Institut, Heinrich-Buff-Ring 16, Justus-Liebig-Universität Giessen, D-35392 Giessen, Germany.
Hofstaetter
Albrecht
A
Leiter
Frank
F
Zhou
Huijuan
H
Henecker
Frank
F
Meyer
Bruno K
BK
Orlinskii
Sergei B
SB
Schmidt
Jan
J
Baranov
Pavel G
PG