High-performance planar-type electron source based on a graphene-oxide-semiconductor structure
High-performance planar-type electron source based on a graphene-oxide-semiconductor structure
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DOI：
10.1063/1.5091585
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发表时间：
2019-05-27
影响因子：
4
通讯作者：
Mimura, Hidenori
中科院分区：
文献类型：
--
作者：
Murakami, Katsuhisa;Miyaji, Joji;Mimura, Hidenori
采用低压化学气相沉积法在氧化层上直接合成石墨烯，制备了石墨烯-氧化半导体（GOS）平面型电子源。利用石墨烯电极抑制最顶层栅极内的电子非弹性散射，最大电子发射效率达到32.1%。电子发射电流密度为100mA/cm(2)，电子发射效率为16.2%。电子能量分布很好地符合麦克斯韦-玻尔兹曼分布，表明电子在电子源内处于热平衡状态。发射电子的半最大能展全宽约为1.1eV。在直流工作超过42h后，电子发射效率没有下降。因此，GOS平面型电子源有潜力成为一种优秀的电子显微镜电子枪。
A graphene-oxide-semiconductor (GOS) planar-type electron source was fabricated by direct synthesis of graphene on an oxide layer via low-pressure chemical vapor deposition. It achieved a maximum electron emission efficiency of 32.1% by suppressing the electron inelastic scattering within the topmost gate electrode using a graphene electrode. In addition, an electron emission current density of 100mA/cm(2) was observed at an electron emission efficiency of 16.2%. The electron energy spread was well fitted to Maxwell-Boltzmann distribution, which indicates that the emitted electrons are the thermally equilibrium state within the electron source. The full-width at half-maximum energy spread of the emitted electrons was approximately 1.1eV. The electron emission efficiency did not deteriorate after more than 42h of direct current operation. Thus, the GOS planar-type electron source has the potential to be an excellent electron gun for electron microscopy.