X-ray photoelectron spectroscopy (XPS) was used to study the microporous surface elements change in content and
chemical states of microchannel plates before and after hydrogen reduction. The results show that the oxygen charge
states include mixture of bridging oxygen (BO), non-bridging oxygen (NBO), and hydrogen oxide (-OH), and BO is the
main charge state, that Si, Pb and Bi are also bonded with F to produce fluoride except bonding with oxygen before
hydrogen reduction. After hydrogen reduction, the binding state of O and Si unchanged. The [BO] and [NBO] decrease,
and [OH] increases obviously. Si fluoride reacts with H2O and produces amounts of ≡Si-O- at high temperature. The lead
exists in mixture of Pb0 and Pb2+, and the Bi mainly exists in bond of Bi0 in surface region of the reduced samples. The signals of K2p and Na1s emerged again in the reduced samples. It is the change in content and chemical states of
microchannel plates after hydrogen reducing processing that the secondary electron emission yield after reduction is 1.5
times higher than that of samples before reduction, and the bulk resistivity obviously drops by 3~4 order.
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