【作者】 朱京涛； 赵明； 尹钢； 赵利； 陈德应；

【Author】 ZHU Jing-Tao, ZHAO Ming, YIN Gang, ZHAO Li Surface Physics Laboratory (National Key Laboratory), Physics Department, Fudan University, Shanghai 200433 CHEN De-Ying Institute of Optical-electronics technology, Harbin Institute of Technology, Harbin 150001

【机构】 复旦大学物理系表面物理国家重点实验室； 哈尔滨工业大学光电子技术研究部；

【摘要】 在特定的气体氛围下,用一定能量密度的超短脉冲激光连续照射固定的硅片表面,可在硅表面产生准规则排列的微米量级锥形尖峰结构,制备出“黑硅”新材料。不同气体氛围下超短激光脉冲微构造硅表面的实验表明,激光脉宽和背景气体对表面微构造的形成起着决定性作用。研究了在SF6气体氛围中,皮秒和飞秒激光脉冲作用下硅表面微结构的演化过程,在皮秒激光脉冲作用下,尖峰结构形成之前硅片表面先熔化;而飞秒激光脉冲作用下尖峰的演化过程中始终没有出现液相,实验结果表明,利用皮秒和飞秒激光脉冲微构造硅表面,均可在硅表面形成准规则排列的微米量级尖峰结构,但不同脉冲宽度的激光与硅表面相互作用的物理机制并不相同。初步研究了“黑硅”材料的光吸收性质,该材料对波长0.25～9μm的光波有强烈的吸收,这种新材料在光电探测器、太阳能电池等器件制造领域有着巨大的潜在应用价值。更多还原

【Abstract】 We report that an array of sharp conical spikes formed on the silicon surface under the cumulative ultra-short laser pulses irradiation in different ambient atmospheres. New material is fabricated called “black silicon”. The experimental results suggest that the physical mechanisms of conical spikes evolutions under picosecond (ps) and femtosecond (fs) laser irradiations are different. The formation of spikes arrays depends on the pulse duration and ambient atmosphere. Under the ps laser irradiation, silicon surface is melted before the spike arrays formed, while under the fs laser irradiation, the formation of spike array does not pass through the liquid phase. It seems that the electron-phonon interaction and the heat diffusion effect play the role on the microstructure evolution of Si surface under laser pulse irradiation. The material possesses the enhancement of infrared absorption promising for new device applications, such as solar cells, infrared photo-detector.更多还原