强流脉冲电子束轰击对单晶Si表面形貌的影响

摘要

[111]- and [001]-Si single crystals were bombarded by high current pulsed electron beam (HCPEB) in energy density of 3-4 J/cm2.Surface morphologies of the irradiated Si samples were investigated with scanning electron microprobe.The results show that many craters were formed on the surface by 3 J/cm2 HCPEB.At 4 J/cm2energy density,microcracks occurred on the bombarded surface.The shape of the microcracks was closely related to the crystal orientation of the bombarded sample.Under the HCPEB bombardment,severe plastic deformation occurred on the irradiated surface.Deformed shear bands were presented on the surface of [ 111 ]-Si,whereas the microbands are the dominating deformed microstructures on the bombarded surface of [001]-Si.In addition,a mass of micropores below 100 nm formed on the deformed regions,which provides a possibility of fabricating the surface porous materials.%用强流脉冲电子束技术对两种取向的单晶Si片进行了表面轰击,对电子束诱发的表面形貌进行了分析.实验结果表明,当能量密度～3 J/cm2时,轰击表面开始形成大量的熔坑.能量密度～4 J/cm2时,表面开始出现微裂纹,微裂纹的形态与单晶Si的晶体取向密切相关;强流脉冲电子束轰击能够诱发表层强烈的塑性变形,[111]取向单晶Si表面出现剪切带结构,而[001]取向单晶Si表面变形结构则以微条带为主;此外,变形区域内还出现大量<100 nm的微孔洞形貌,这些微孔洞的形成为制备表面多孔材料提供了可能.