Discussion of the improving secondary electron emission coefficient

The design of lengthening the diffusion lengths of negative electron affinity emitter GaAs was introduced; the secondary electron emission coefficients of normal GaAs was compared with that of specially designed GaAs.The conclusion shows that the deviation of the two kinds of secondary electron emission coefficient is smaller if primary electron incident energy is lower （less than 10 keV）and that the deviation of the two kinds of secondary electron emission coefficient is larger if primary electron incident energy is higher（more than 20 keV）.With the primary electron incident energy becoming higher, the deviation of the two kinds of secondary electron emission coefficient becomes larger．