A theoretical model which takes into account thermally stimulated luminescence (TSL), conductivity (TSC) and exoelectronic emission (TSEE) is proposed in this article. The model is established for the case of a single type of electron trap, a single type of recombination centre and in the presence of thermally disconnected traps. It generalizes the model of Lewandowski and McKeever by taking the TSEE phenomenon into consideration. TSEE is described as resulting from the thermionic effect and so the model applies only to a thin solid film about 10 nm thick. As an application example, the influence of various parameters involved in the model on peak shape and position is investigated.

A method of estimating the electron affinity value of an insulator has been developed. The measurement was carried out from the simultaneous detection of thermoluminescence and thermostimulated exoelectronic emission (TSEE) curves presented by the material. This is possible when the TSEE phenomenon is governed by the thermoionic model and when the electron concentration of the considered trap becomes weaker than that of thermally disconnected traps. The application to an -alumina single crystal shows that the electron affinity can be evaluated as from the thermostimulated peak at 275 K and at from the thermostimulated peak at 440 K. The validity of the model and the signification of the results are discussed.

In recent work we described a method which allowed the estimation of the effective electron affinity of α-alumina. The interpretation of these results has given rise to the comment from Dr Käämbre. Here, we develop some arguments in response to this comment.

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A systematic study of TSEE curves obtained after UV or X irradiations at 77 K from alumina samples of various origin is reported. These curves are systematically compared with TL glow curves recorded in similar conditions. Nine positions for thermostimulated peaks are detected in the 77 to 600 K range. These peaks appear with various occurrence frequencies. Except for the first peak (100 K, peak A) which does not exist in the majority of the TSEE curves recorded, the main TSEE peaks coincide fairly well with the correspondent TL peaks. A mechanism is proposed to interpret the behaviour of peak A.