Blue electroluminescence of diamond thin film has already been investigated by some authors. To our knowledge, ultraviolet electroluminescence of diamond thin film has not been reported so far. We have prepared an electroluminescence device with a Blue electroluminescence of diamond thin film has already been investigated by some authors. To our knowledge, ultraviolet electroluminescence of diamond thin film has not been reported so far. We have prepared an electroluminescence device with a