Excited Terminal States of a Bound Exciton-Donor Complex in ZnO

The excited terminal states of a bound exciton-donor complex in ZnO have been investigated. Using an electron effective mass of $0.19m_e$, a good theoretical fit to the experimental data was achieved. A donor ionization energy of 0.035 eV was calculated from the effective-mass approximation. Experimentally, the donor ground-state binding energy is 0.052 eV, determined on the assumption that the $n=2\mathrm{}$ excited state is effective-mass-like. An electron $g$ value of ${1.9}_5$ and a hole $g$ value of 1.2 were determined for the ground state from Zeeman studies.