镶嵌结构锗纳米晶电输运的研究  

Electron-Transport Properties of Ge Nanocrystals Embedded Structure

作　　者：张盛华[1] 卢铁城[2] 敦少博[2] 胡强[2] 赵建君[2] 何捷[2] 

机构地区：[1]桂林医学院物理教研室,广西桂林541004 [2]四川大学物理系.辐射物理及技术教育部重点实验室,成都610064

出　　处：《四川大学学报（自然科学版）》2006年第3期622-626,共5页Journal of Sichuan University(Natural Science Edition)

摘　　要：利用离子注入然后退火的方法制备了镶嵌有锗纳米晶的二氧化硅复合薄膜,从拉曼散射和透射电镜测量了解到薄膜中镶嵌有5~7nm大小的锗纳米晶层.研究了锗纳米晶层在常温和低温下的电输运性质.结果表明:锗纳米晶在100K^300K温度范围内符合莫特变程跳跃电导(VRH)导电,100K以下的低温电导基本上是一常数,导电主要是电子在相邻纳米晶之间的直接跃迁;经退火可消除离子注入引入的缺陷,能增加薄膜的电导;对由3×1017cm-2注量锗离子注入制备的薄膜观察到半导体向金属导电的转变.Ge nanocrystals embedded in SiO2 films were prepared by ion implantation and subsequent annealing. Ge nanocrystals were measured by laser Raman scattering and high resolution TEM. The electron transport properties of samples in room temperature and low temperature were studied, respectively. The conductivity was found to vary with the temperature as In σ∝T^-1/4 over a wide temperature range, indicative of the conduction by the variable range hopping （VRH） mechanism. Conductivity increases after samples were annealed. When the concentration of Ge nanocrystals increases enough, metallic transformation is observed.

关 键 词：锗纳米晶 电输运 低温电导 

分 类 号：O484.3[理学—固体物理]