Advanced Coating Technology for Enhanced Performance of Microchannel Plates for UV Detectors

In this NASA SBIR Phase I proposal we propose to apply a highly conformal coating of ZnO and AlN or a double layer of GaN to the surface and internal pore walls of conventional microchannel plates (MCP). This will lead to enhanced secondary electron emission (SEE) and, thus, improve MCP gain for UV /X-ray detectors. The ZnO/ALN(GaN) hetrostructure using nano ZnO needles as templates has been demonstrated to exhibit significantly higher SEE yield for electrons, ions and X-ray beams. The coatings will be carrid out by atomic layer deposition (ALD). The key advantages of ALD include 1)super conformity of coatings and nearly 100% step coverage on very high aspect ratio substrates, which is well suited for coating highly porous MCP wafers with a aspect ration ~100; 2)super thickness and composition control; 3)continuous and pin hole free quality films; and 4) easy to scale up for large area deposition at low cost. To the best of our knowledge this is the first time the advanced ALD process has been proposed as a way of improving UV detector performance of MCPS. If successful, this technology will provide an effective method of modifing the MCP surfaces by coating them with high SEE yield films that will dramatically improve the gain of conventional MCPs. This will enhance the performance of UV detectors required for various NASA missions.