摘要
脉冲激光烧蚀（PLA）法制备硅纳米颗粒的过程中,缓冲气体压力是影响纳米颗粒尺寸最主要的参数之一。研究通常认为,随着缓冲气体压力的增大,纳米颗粒的尺寸相应增大。经扫描电镜（SEM）观察和粒度统计分析发现,在50~100 Pa的氩气压力范围内,制备所得的硅纳米颗粒尺寸均匀,且随氩气压力增大而减小。结合实验参数对脉冲激光烧蚀法的动力学做理论分析,得出压力和硅纳米颗粒直径关系式,与实验结果吻合较好。对此系列硅纳米颗粒用280 nm光做室温光致发光（PL）测试,发现蓝紫光区的光致发光现象。在50 Pa气压下样品具有372 nm和445 nm的双峰结构,而在70 Pa和100 Pa气压下样品只有紫光区的明显峰,分别位于379 nm和393 nm。该蓝紫光区的光致发光谱归结为硅纳米颗粒表面氧化层的表面态效应。
The buffer gas pressure is one of the most important parameters which influence the size of nanoparticles in the synthesized process by pulse laser ablation（PLA）.Usually speaking,the size of nanoparticles increases with the increase of buffer gas pressure.In this report,according to the scanning electron microscopy（SEM） measurements and corresponding statistic results for particles size of about 10 nm,it can be obtained that,the size of silicon nanoparticles decreases with the increasing of the gas pressure in the range of 50～100 Pa,and a relative expression between the gas pressure and the size of the silicon nanoparticles can be given,which describes the experimental phenomenon properly.The photoluminescent（PL） properties of silicon nanoparticles are investigated by photoluminescence spectroscopy with a wavelength of 280 nm at room temperature,and the violet and blue emissions are gained.A double peak structure at 372 nm and 445 nm appears in the sample synthesized by the gas pressure of 50 Pa.While the gas pressure increases to 70 Pa or 100 Pa,the peak in blue region disappears and the peak in violet region shifts to 379 nm and 393 nm corresponding to the samples synthesized by gas pressure of 70 Pa and 100 Pa respectively.These photoluminescent emissions are attributed to the surface state effect from the oxidized layer at the surface of the silicon nanoparticles.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2010年第3期882-886,共5页
Chinese Journal of Lasers
关键词
激光技术
硅纳米颗粒
光致发光
脉冲激光烧蚀
缓冲气体压力
laser technique
silicon nanoparticles
photoluminescence
pulsed laser ablation
buffer gas pressure
