Study on enhancement in emission current of plane-type tunneling cathodes by controlling the work function

1.测量了有、无Cs涂层的MOS隧穿阴极的栅压-发射电流特性和发射电子的能量损耗。这些特性表明，控制逸出功是提高MOS隧穿阴极发射电流的最有效途径.我们制作了一种新型的双栅MOS隧穿阴极。实验证实了双栅MOS阴极的有效功函数是可以控制的.我们已经成功地证明了场致发射体的有效功函数与适当的薄膜涂层变得低于原来的场致发射体。研究还表明，带涂层的场发射体的有效功函数取决于场发射体原始材料与涂层材料之间的电子势垒、涂层材料的介电常数和电子亲合势.制备了厚度分别为2.83nm和2.83nm的GaAs/AlAs单量子阱共振隧穿发射极。我们已经观察到的发射电流，这是强烈相关的负电阻，由于共振隧穿效应。这表明，发射电流被认为是来自共振隧穿效应。

1. We have measured gate voltage - emission current characteristics and energy destitutions of the emitted electrons for MOS tunneling cathodes with and without Cs coating. These characteristics reveal that controlling the work function is the most useful for enhancing the emission current in the MOS tunneling cathodes.2. We have fabricated the new MOS tunneling cathode which has two gate electrodes. We have experimentally confirmed that it is possible to control the effective work function in the MOS cathode with two gate electrodes.3. We have successfully demonstrated that the effective work function of the field emitters with an appropriate thin-film-coating becomes lower than that of the original field emitters. We also reveal that the effective work function of the field emitters with the coating is determined by the potential barrier for injected electrons between the original material of the field emitter and the coating material, the dielectric constant and the electron affinity of the coating material.4. We have fabricated resonant tunneling emitters with a single quantum well of GaAs/AlAs, whose thicknesses are 2.83nm and 2.83nm, respectively. We have observed the emission current which is strongly related to the negative resistance due to the resonant tunneling effect. This indicates that the emission current is considered to come from the resonant tunneling effect.