Abstract In this study, metal-based asymmetric electrodes for field emission (FE) diodes were fabricated. E-beam lithography generated a minimal anode–cathode distance of approximately 24 nm. Measurements in the air displayed Fowler–Nordheim tunneling under a potential less than 0.5 V. The design enabled the maximal electric field at acute terminals made of multiple triangles as cathode, thus generating high acceleration for the forward current. By contrast, the maximal electric field occurred at blunt terminals made of multiple semicircles as cathode, thus generating low acceleration in reverse bias. Furthermore, the reverse bias could be subject to electron scattering because of the operation in the air, leading to a lower electric current than the forward bias. The forward/reverse current ratio increased with increasing applied voltage. Compared with other asymmetric FE devices, the FE diodes developed in this work can effectively enhance the forward/reverse current ratio, suggesting that asymmetric cathode and anode design can serve as an FE diode. Finite element modeling showed that the electric field and speed were maximal at apices of the multiple triangular electrodes used as cathode and minimal on flat edges of the multiple semicircular electrodes used as cathode, thereby resulting in asymmetric electron flow. The results supported the potential application of metal-based asymmetric electrodes to FE diodes.

中文翻译：

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在空气中工作的金属基非对称场发射二极管

摘要 在这项研究中，制造了用于场发射 (FE) 二极管的金属基不对称电极。电子束光刻产生大约 24 nm 的最小阳极-阴极距离。空气中的测量显示，在低于 0.5 V 的电位下，Fowler-Nordheim 隧穿。该设计在由多个三角形作为阴极组成的锐端处实现了最大电场，从而为正向电流产生了高加速度。相比之下，最大电场出现在由多个半圆作为阴极的钝端处，因此在反向偏压下产生低加速度。此外，由于在空气中的操作，反向偏压可能会受到电子散射，导致电流低于正向偏压。正向/反向电流比随着施加电压的增加而增加。与其他非对称 FE 器件相比，本工作开发的 FE 二极管可以有效提高正向/反向电流比，表明非对称阴极和阳极设计可以用作 FE 二极管。有限元建模表明，电场和速度在用作阴极的多个三角形电极的顶点处最大，在用作阴极的多个半圆形电极的平坦边缘处最小，从而导致不对称的电子流。结果支持金属基不对称电极在 FE 二极管中的潜在应用。有限元建模表明，电场和速度在用作阴极的多个三角形电极的顶点处最大，在用作阴极的多个半圆形电极的平坦边缘处最小，从而导致不对称的电子流。结果支持金属基不对称电极在 FE 二极管中的潜在应用。有限元建模表明，电场和速度在用作阴极的多个三角形电极的顶点处最大，在用作阴极的多个半圆形电极的平坦边缘处最小，从而导致不对称的电子流。结果支持金属基不对称电极在 FE 二极管中的潜在应用。