Mutsukawa Ren, Takao Yoshinori, Murata Hiromasa, Nagao Masayoshi, Murakami Katsuhisa
Department of Mechanical Engineering, Materials Science, and Ocean Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan.
National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan.
ACS Omega. 2025 May 22;10(21):21731-21737. doi: 10.1021/acsomega.5c01310. eCollection 2025 Jun 3.
Graphene-oxide-semiconductor (GOS) planar electron-emitting devices with an aluminum oxide (AlO) protective layer were found to improve oxidation resistance and to be capable of emitting electrons through a protective film on the device. An electron-transparent oxidation resistance layer for the GOS device was achieved with a uniform 3 nm AlO deposited by atomic-layer deposition at a low temperature of 100 °C after precleaning with HO. A high electron emission current density of 1.01 mA/cm and a high electron emission efficiency of 0.49% were obtained from the GOS electron-emitting device with the uniform 3 nm AlO protective film. The energy distribution of the electrons emitted from the GOS device with an AlO protection layer was higher than the work function of the graphene electrode, which indicated that the primary factor in the degradation of electron emission efficiency of the GOS device by the AlO protection layer was not the energy loss of the emitted electrons due to inelastic electron scattering within AlO but the electron backscattering at the protection layer due to elastic electron scattering. These results suggest that the electron emission efficiency and current density of oxygen-tolerant GOS devices could be further improved by a uniform AlO protective layer with a thickness below the mean free path of electron elastic scattering within AlO.
具有氧化铝（AlO）保护层的氧化石墨烯-半导体（GOS）平面电子发射器件被发现可提高抗氧化性，并且能够通过器件上的保护膜发射电子。在使用HO进行预清洁后，通过在100°C的低温下通过原子层沉积沉积均匀的3nm AlO，实现了用于GOS器件的电子透明抗氧化层。从具有均匀3nm AlO保护膜的GOS电子发射器件获得了1.01mA/cm的高电子发射电流密度和0.49%的高电子发射效率。具有AlO保护层的GOS器件发射的电子的能量分布高于石墨烯电极的功函数，这表明AlO保护层导致GOS器件电子发射效率下降的主要因素不是由于AlO内非弹性电子散射导致发射电子的能量损失，而是由于弹性电子散射导致的保护层处的电子背散射。这些结果表明，通过厚度低于AlO内电子弹性散射平均自由程的均匀AlO保护层，可以进一步提高耐氧GOS器件的电子发射效率和电流密度。
