Investigation of the secondary emission characteristics of CVD diamond films for electron amplification

Chemical vapour deposition (CVD) diamond offers great potential as a low-cost, high-yield, easily manufactured secondary electron emitter for electron multiplication in devices such as photomultiplier tubes. Its potential for high secondary electron yield offers several significant benefits for these devices including higher time resolution, faster signal rise time, reduced pulse height distribution, low noise, and chemical stability.We describe an experiment to characterize the secondary emission yield of CVD diamond manufactured using different processes and process parameters and discuss the degradation of secondary electron yield and experimental difficulties encountered due to unwanted electron beam-induced contamination. We describe techniques utilized to overcome these difficulties, and present measurements of secondary yield from CVD diamond dynodes in reflection mode.We discuss the application of CVD diamond dynode technology, both in reflection and transmission mode, to advanced high-speed imaging and photon-counting detectors and describe future plans in this area.