Re-activation of an inactive Ge(Li) detector left for long time at room temperature

The two techniques of re-activating or fabricating a Ge(Li) detector simpler than the usual ones are presented. One is applied in the first stage, which is Li-evaporation onto Ge-crystal and thermal diffusion into the crystal. The crystal is heated directly by an electric current and the Li-evaporation efficiency is raised by means of electric fields applied between the crystal and the evaporators and between these two and the surrounding reflector electrode. The other is applied in the final stage of the so-called ''clean-up'' process. The Q-factor as a function of the applied bias voltage measured simultaneously with a capacitance can be used as a measure of the degree of quality (characteristic) which governs the detector resolution. By the techniques, re-activation was successfully carried out of an inactive detector left for long time at room temperature. They are applicable to re-activation of the deteriorated detector due to bombardment of fast neutron or charged particles. The procedure of re-activation and the results are described. (auth.)