Uniformity of AZO conductive film on microchannel plate by atomic layer deposition and effect of annealing on bulk resistance

Abstract

AZO(ZnO/Al _2 O _3 ) conductive films were deposited in the microchannel of microchannel plate (MCP) by atomic layer deposition (ALD). The prepared films were characterized, including analysis of the thickness and composition uniformity of AZO films. The MCP bulk resistance was also measured, and the effect of annealing treatment on bulk resistance was investigated. The results suggest that the use of trimethylaluminum in the preparation of AZO composite film within the microchannel of MCP leads to corrosion of ZnO, resulting in non-uniformity in film thickness and incorrect composition of the film. The problem was resolved by increasing the pulse time of trimethylaluminum to 500 ms, resulting in the successful preparation of an AZO film with a uniform thickness and composition in the microchannel. After annealing, the bulk resistance of MCP increases while the variation of bulk resistance with voltage decreases. Specifically, the bulk resistance of the MCP having a ZnO/Al _2 O _3 ratio of 7/2 only experiences changes of the same order of magnitude (∼10 ^8 Ω) after undergoing a 60-minute annealing process in N _2 at 300 °C, thus satisfying the requirements of MCP.

Keywords

• atomic layer deposition
• microchannel plate
• AZO conductive films
• annealing
• bulk resistance