Influence of input electrode of micro-channel plate on opening area ratio and its improvement北大核心CSCD

微通道板作为一种关键的电子倍增器件,广泛应用于诸多领域。分析了NiCr膜层作为微通道板的输入端电极时,对微通道板开口面积比的影响,建立了理论模型,计算了膜层厚度、镀膜深度等参数对开口面积比的影响。开展了2种减小开口面积比损失的镀膜研究:一是进行工艺调整,减弱合金蒸发的分馏效应,降低电极膜层的电阻率,开口面积比损失量降低约2%;二是改变镀膜方式,使用Ni、Cr金属单质镀制叠层薄膜,在镀膜过程中调控镍、铬的比例,将输入端电极中镍比例升高,同样可以降低电极膜层的电阻率,在满足面电阻要求的前提下,可减薄输入端膜层至86 nm,与300 nm厚度的常规镍铬合金膜层相比,MCP输入端的开口面积比损失量降低3%~4%,MCP增益提升6%。

Influence of input electrode of micro-channel plate on opening area ratio and its improvement

As a key electron multiplier, the micro-channel plate is widely used in many fields. The effect of NiCr film as the input electrode of micro-channel plate on the opening area ratio of micro-channel plate was analyzed. A theoretical model was established, and the effects of coating thickness, coating depth and other parameters on the opening area ratio were calculated. Two kinds of coating research were carried out to reduce the loss of opening area ratio. One way, the process was adjusted to weaken the fractionation effect of alloy evaporation, reduce the resistivity of electrode film layer, and the loss of opening area ratio was reduced by about 2 percentage points. Another way was to change the coating method, the Ni and Cr metal were used to prepare laminated films, regulate the proportion of Ni and Cr in the coating process, increase the proportion of Ni in the input terminal electrode, and also reduce the resistivity of the electrode film. On the premise of meeting the surface resistance requirements, the input terminal film could be thinned to 86 nm. Compared with the conventional Ni-Cr alloy film with a thickness of 300 nm, the loss of the opening area ratio of the MCP input terminal was reduced by 3~4 percentage points, and the MCP gain was increased by 6%.