湿法化学刻蚀法制备硅纳米线

发布时间：2018-07-07 07:59

  本文选题：硅纳米线 + 湿法化学刻蚀法　； 参考：《东北师范大学》2010年硕士论文

【摘要】： 由于硅是间接带隙半导体,T=0K时,带隙宽度Eg=1.17eV,T=300K时,带隙宽度Eg=1.14eV,其导带底和价带顶位于波矢量空间的不同位置,在满足动量守恒的条件下,只有借助声子作用才能实现间接带隙半导体跃迁发光。但一维硅纳米线具有高表面活性和量子限制效应,可获得较强的发光,因而硅纳米线的研究极为重要。 本论文利用选择性刻蚀方法,采用湿法化学刻蚀法制备硅纳米阵列结构,讨论了生长时间、氢氟酸浓度、硝酸银溶液浓度、反应温度对硅纳米线形貌的影响,以及对硅纳米线Raman光谱的影响。 通过分析不同条件下制备的硅纳米线的SEM图像,当反应温度为50℃,5mol/L氢氟酸,0.02mol/L AgNO_3溶液,且氢氟酸与硝酸银的体积比V(HF):V( AgNO 3)=1:4,生长1h以后制备的硅纳米线形貌最好,形成了典型的纳米线阵列结构,纳米线长度为30微米左右,直径为15-50nm。样品的Raman主峰位于519.2 cm~(-1) ,半高宽为3.1 cm~(-1)。 高氢氟酸浓度和高生长温度生长的硅纳米线,由于样品中存在大量的缺陷,造成硅纳米线中声子频率变化,导致声子寿命减小,谱线的半高宽增大,从而观察到5.5mol/L氢氟酸生长的样品具有高达7.6 cm~(-1)谱线半高宽以及75℃生长的样品具有高达5.7 cm~(-1)的谱线半高宽。
[Abstract]:Because silicon is an indirect band-gap semiconductor (T _ (0) K), the band gap width (E _ (1) 17eV ~ (T) ~ (300) K) is 1.14 EV. The bottom of the conduction band and the top of the valence band are located at different positions in the wave vector space, and the momentum conservation is satisfied. Only by phonon interaction can indirect band gap semiconductor transition luminescence be realized. However, the one-dimensional silicon nanowires have high surface activity and quantum confinement effect, so the study of silicon nanowires is very important. In this paper, silicon nanowires were prepared by wet chemical etching with selective etching method. The effects of growth time, concentration of hydrofluoric acid, concentration of silver nitrate solution and reaction temperature on the morphology of silicon nanowires were discussed. And the effect on Raman spectra of silicon nanowires. The SEM images of silicon nanowires prepared under different conditions were analyzed. When the reaction temperature was 50 鈩，

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