Orientation dependence of electron–irradiation damage in zinc oxide

The threshold voltage for zinc displacement in ZnO by electron irradiation lias been determined by high–voltage electron microscopy as a function of incident orientation from the [2110] to both the [0001] and [000T] directions. It is found that the threshold voltage is a minimum (∼700kV) in the [2110] direction and a maximum (∼1100kV) in the [0001] and [000T] directions without showing polarity effects. The result is interpreted in terms of the crystal structure of ZnO.