Development of UV image intensifier tube with GaN photocathode

We developed an UV image intensifier tube with a GaN photocathode in semi-transparent mode. In UV spectroscopy and low-light-level UV-imaging applications, there are strong demands for improved detectors which have higher quantum efficiency, low dark current, sharper wavelength cut-off response, and stable and robust characteristics. III-Nitrides semiconductor is one of the promising candidate materials to meet these demands. We developed a GaN photocathode which is epitaxially grown by MOCVD method. It has flat and high quantum efficiency from 200 nm to 360 nm. The cathode is incorporated into an image intensifier tube, which shows good gating performance and fine imaging resolution. With these improved performances, the UV image intensifier tube with GaN photocathode will expand its application fields to include UV spectroscopy and UV-imaging in low light.