Au Doping Effect on the Secondary Electron Emission Performance of MgO Films

Abstract

Au-doped MgO films were prepared by reactive sputtering of individual Mg and Au targets, and the Au doping effect on the electron-induced secondary electron emission (SEE) performance was explored by means of surface analysis, first-principle calculation, and electrical characteristic measurement. The results show that the size enlargement of MgO grains and the reduction of surface work functions induced by Au doping are the main reasons for the increase of the SEE coefficient (δ). Additionally, the superior SEE degradation property of the Au-doped MgO film under continuous electron bombardment results from the improvement of electrical conductivity. Through the optimization of Au doping concentration (x), Au-doped MgO film with an x value of 3.0% was found to have the best SEE performance due to its highest SEE coefficient and longest duration of maintaining a relatively high SEE coefficient; its maximum δ value reached 11.5—an increase of 32.2% in comparison with the undoped one.

Mixed Films Based on MgO for Secondary Electron Emission Application: General Trends and MOCVD Prospects

“…There is a sufficient number of works where enhancement of SEEC of the relatively thick (>10 nm) MgO films was observed due to lowering EA due to the surface embedded metal. So, composites such as MgO/Au and Au/MgO modified by Zn and Al, showed high SEE, but despite modifying MgO, the films remained to be unstable during functioning [17][18][19][20][21][22][23][24]. The ALD fabrication of the Al 2 O 3 /MgO and MgO/Nb/MgO laminated composites with encapsulated MgO and nanoscale Nb layers was of interest for coating due to enhancement of SEEC [25,26].…”

Substrate Temperature Dependent Microstructure and Electron-Induced Secondary Electron Emission Properties of Magnetron Sputter-Deposited Amorphous Carbon Films

“…Secondary electron emission (SEE) from solid materials has attracted a lot of attention due to its widespread applications in many technology fields such as night vision, microscopic analysis, satellite navigation, mass spectrum, and space exploration [1,2,3,4,5], and SEE usually plays a role of signal amplification in these applications. But in some cases, SEE may produce a negative effect on the normal operations of some special instruments or equipments.…”