A simple physical metal mask is efficiently employed to obtain an array of silicon (Si) nanowires (Si-NWs) on a Si substrate grown using the hot filament chemical vapor deposition route. Well adhered and uniform coating of different thicknesses (20 and 50 nm) of lanthanum hexaboride (LaB₆) on Si-NWs was obtained using electron beam evaporation technique. The thickness of LaB₆ coating was estimated from ellipsometry measurement. Structural, morphological, and chemical properties of the LaB₆ coated Si-NWs (LaB₆@Si-NWs) arrays were revealed using x-ray diffraction, field emission scanning electron microscope, transmission electron microscope, Raman spectroscopy, and x-ray photoelectron spectroscopy. Field electron emission characteristics of pristine Si-NW array and LaB₆ coated Si-NWs array emitters were studied in planar diode configuration at a base pressure of 1 × 10⁻⁸ mbar. The values of turn-on field (current density ∼1 μA/cm²) were observed as ∼2.2, 1.2, and 1.6 V/μm for pristine Si-NWs, LaB₆@Si-NWs_20, and LaB₆@Si-NWs_50 array emitters, respectively. Furthermore, maximum emission current densities of ∼1276.81, 2763.64, and 2231.81 μA/cm² have been extracted from the pristine Si-NWs, LaB₆@Si-NWS_20, and LaB₆@Si-NWS_50 array emitters at an applied field of 3.1, 2.7, and 2.7 V/μm, respectively. The LaB₆@Si-NWS_20 array emitter demonstrated superior FEE properties as compared to the pristine Si-NWs and LaB₆@Si-NWS_50 emitters. Furthermore, LaB₆@Si-NWS_20 emitter depicted very good emission current stability tested at a preset value of 1 μA over a duration of 3 h. The enhanced FEE performance exhibited by the LaB₆@Si-NWs_20 array emitter is attributed to reduction in effective work function and enhanced electron tunneling probability across the LaB₆–Si interface.

中文翻译：

---

LaB6 涂层硅纳米线阵列的厚度相关场发射研究

一个简单的物理金属掩模被有效地用于在使用热灯丝化学气相沉积路线生长的 Si 基板上获得硅 (Si) 纳米线 (Si-NW) 阵列。使用电子束蒸发技术在 Si-NW 上获得了不同厚度（20 和 50 nm）的六硼化镧 (LaB ₆ )附着良好且均匀的涂层。_{LaB 6}涂层的厚度由椭圆光度法测量估计。LaB ₆涂层 Si-NWs (LaB ₆@Si-NWs) 阵列使用 X 射线衍射、场发射扫描电子显微镜、透射电子显微镜、拉曼光谱和 X 射线光电子能谱进行揭示。原始 Si-NW 阵列和 LaB ₆涂层 Si-NWs 阵列发射器的场电子发射特性在平面二极管配置中在 1 × 10 ^-8  mbar的基础压力下进行了研究。对于原始 Si-NW、LaB ₆ @Si-NWs_20 和 LaB ₆ @Si ，观察到的开启场值（电流密度 ∼1  μ A/cm ²）为 ∼2.2、1.2 和 1.6 V/ μ m -NWs_50 阵列发射器，分别。此外，最大发射电流密度为 ~1276.81、2763.64 和 2231.81 μ A/cm ²已从原始 Si-NW、LaB ₆ @Si-NWS_20 和 LaB ₆ @Si-NWS_50 阵列发射器中提取，应用场分别为 3.1、2.7 和 2.7 V/ μm。与原始 Si-NW 和LaB _{6 @Si-NWS_50 发射器相比，LaB 6} @Si-NWS_20 阵列发射器表现出优异的 FEE 特性。此外，LaB _{6 @Si-NWS_20 发射器表现出非常好的发射电流稳定性，在 3 小时的持续时间内以 1} μ A的预设值进行测试 。LaB _{6展示的增强型 FEE 性能}@Si-NWs_20 阵列发射器归因于有效功函数的减少和 LaB ₆ –Si 界面上电子隧穿概率的增加。