The development of NTD technology in the Institute of Atomic Energy

The plan for developing NTD technology in the Institute of Atomic Energy began in 1979. Experiments on the irradiation conditions, irradiation facilities, and annealing after irradiation bave been carried out at the Swimming Pool Reactor (SPR) at the Institute. The initial technology developed was successfully used for production of NTD Si. Subsequently, the SPR was modified to install some additional irradiation facilities, and the commercial irradiation of NTD silicon ingots was initiated in 1980. The capability for irradiating silicon was also included during the reconstruction of the Heavy Water Research Reactor at the Institute. In order to irradiate large diameter silicon ingots, four vertical tubes each with a diameter of 120 mm were installed in the heavy water reflector. Two sets of irradiation facilities along with transportation and cleaning equipment were in use in 1981