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氧化钇阴极广泛应用于一系列超高频器件中。而其发射机理尚不清楚,尤其是在激活时体积和表面对阴极热发射活性形成的贡献问题。单晶Y_2 O_3是用定向结晶法来获得。使用单晶能避免与发射涂层的细结晶度、孔隙度和粗糙度有联系的效应。此外,利用测量单晶的透射光谱可获得有关体积能量结构变化的信息。本文的目的是估算在晶体激活中所能达到的发射电流增加过程中体积和表面所起的作用。
Yttrium oxide cathode is widely used in a series of UHF devices. The mechanism of its emission is unclear, especially the contribution of volume and surface to the formation of cathodic thermal emissivity at activation. Single crystal Y_2 O_3 is obtained by directional crystallization. The use of single crystals avoids the effects associated with the fine crystallinity, porosity and roughness of the emissive coating. In addition, information on changes in volume energy structure can be obtained by measuring the transmission spectrum of a single crystal. The purpose of this paper is to estimate the effect of volume and surface on the increase of emission current that can be achieved during crystal activation.