Phonon-assisted tunnelling in the electroluminescence exciting process

Experimental results on electroluminescence brightness dependence on temperature and applied voltage for zinc sulphide luminophors are fitted to electron tunnelling rate dependence on temperature and field strength, computed according to the recent phonon-assisted tunnelling theory. A satisfactory agreement of experimental data with theory is observed. It is concluded that the processes of free carrier generation by an electric field play a decisive role in these dependences. On the basis of this conception, the analysis of brightness dependence on temperature and applied voltage allows the determination of the exciting field strength in barriers of the energy of the phonons taking part in the electron tunnelling process.