A HIGH STABLE LONG LIFE-SPAN REFLACTIVE GaAs(Cs, F) PHOTOCATHODE
高稳定长寿命反射式GaAs(Cs,F)光阴极

A Stable surface layer is essential for a high stable long life-span photocathode. Using fluorine instead of oxygen in activating the surface of GaAs substrate, the strong electronegativity of fluorine improved the stability of photocathode. The life-span of reflactive GaAs (Cs, F) photocathode has been up to 8500 hours. Furthermore, its technological reproducibility and anti-contamination ability are better than those of GaAs(Cs, O2) photocathode.