n型多孔硅的制备及其光致发光性能

Preparation of n-PS and its photoluminescence properties

采用双槽电化学腐蚀法于光照条件下在n型单晶硅片衬底上制备多孔硅（n-PS）;在室温下,采用500~700 nm范围内荧光光谱和扫描电镜（SEM）测试系统研究光照、腐蚀时间、电解液含量、腐蚀电流密度及单晶硅掺杂含量等对n-PS的形成、结构形貌和光致发光性能（PL）的影响。研究结果表明,通过光照,能获得具有均匀孔分布和良好发光特性的n-PS,在约600 nm处产生较强荧光峰;随腐蚀时间、HF含量和电流密度增加,PL峰位先发生蓝移,而后又出现红移;PL发光性能呈先增强后减弱变化趋势,分别在腐蚀时间为20 min、HF含量为6%和电流密度为60 mA/cm2时峰强出现极大值;而提高掺杂含量,PL性能降低。

Porous silicon（n-PS） was prepared after being synthesized on monocrystalline silicon wafer substrate by double-cell electrochemical etching method under lighting conditions.The effects of experimental conditions（light effect,etching time,HF content,current density,and doping level of the monocrystalline silicon） on the formation,structure,morphology and PL performance of n-PS were studied using the scanning electron microscopy（SEM） and the photoluminescence（PL） observation（500？700 nm）.The results show that under lighting conditions,a homogenous pore-size distribution and good PL performance of n-PS can be obtained,and a strong fluorescence peak is located at about 600 nm.With the increase of etching time,HF content and current density,the PL peak shows the red shift at first then the blue shift,and the emission intensity first increases and then decreases.The emission intensity appears a maximum value when the corrosion time is 20 min,HF content is 6% and current density is 60 mA/cm2.The PL performance decreases with the increase of the monocrystalline silicon doping content.