Photoluminescence properties of porous silicon layers prepared by electrochemical etching in extremely dilute HF solutions
Photoluminescence properties of porous silicon layers prepared by electrochemical etching in extremely dilute HF solutions
复制标题
DOI：
10.1007/s10800-006-9165-4
复制
发表时间：
2006-07
影响因子：
2.9
通讯作者：
H. Koyama
中科院分区：
文献类型：
--
作者：
H. Koyama
用浓度低至0.03%的HF溶液在p型硅片上制备了发光多孔硅（PSi）层。实验结果表明，在30 min的恒定刻蚀时间下，在低至0.1%的HF浓度下，可以形成具有足够发光效率的PSi层。由于临界电流密度显著降低，只有非常低的蚀刻电流密度≤0.1 mA cm−2才能在0.1% HF溶液中形成发光PSi样品。一个值得注意的结果是，这些低蚀刻电流密度不能用于在浓缩（≥1%）HF溶液中形成发光PSi层。在较宽的HF浓度范围内，分析了PL强度随蚀刻电流密度的变化规律。发光强度由刻蚀电流密度与临界电流密度之比决定，表明硅氧化物的存在在PSi层中发光Si纳米结构的形成中起着重要作用。
Dilute HF solutions with concentrations down to 0.03% have been used to obtain luminescent porous silicon (PSi) layers on p-type Si wafers. The experimental results show that with a constant etching time of 30 min, PSi layers with sufficient luminescence efficiencies can be formed for HF concentrations as low as 0.1%. Because of a significantly lowered critical current density, only very low etching current densities of ≤0.1 mA cm−2can result in the formation of luminescent PSi samples in 0.1% HF solutions. A notable result is that these low etching current densities cannot be used to form luminescent PSi layers in concentrated ( ≥1%) HF solutions. The behavior of PL intensity as a function of etching current density has been analyzed over a wide range of HF concentration. The PL intensity is determined by the ratio of the etching current density to the critical current density, suggesting that the presence of silicon oxides plays an important role in the formation of luminescent Si nanostructures in PSi layers.