With a miniaturization of electrical devices, the gap between electrode becomes lower and lower. In order to optimize the insulation design, the understanding of breakdown phenomenon across micrometer‐scale gap is essential. In this study, breakdown characteristics across micrometer‐scale gap was investigated based on experiment and numerical simulation. The result shows that the breakdown voltage under positive voltage application is 1.5 times higher than the one under the negative voltage application. The polarity effect can be explained by the source of initial electrons. Under negative voltage application, the initial electrons are emitted from the cathode surface based on Fowler‐Nordheim equation. On the other hand, under positive voltage application, the insulator plays an important role on breakdown voltage.

中文翻译：

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击穿特性在微米级表面间隙上的极性影响

随着电气设备的小型化，电极之间的间隙变得越来越小。为了优化绝缘设计，必须了解跨越微米级间隙的击穿现象。在这项研究中，基于实验和数值模拟研究了跨微米级间隙的击穿特性。结果表明，正电压下的击穿电压比负电压下的击穿电压高1.5倍。极性效应可以用初始电子的来源来解释。在负电压下，基于Fowler-Nordheim方程，初始电子从阴极表面发射出去。另一方面，在施加正电压的情况下，绝缘体对击穿电压起着重要的作用。