预非晶化和碳共注入在超浅结工艺中的应用  

Applications of Pre-Amorphization and Carbon Co-Implantation in Ultra Shallow Junction Technology

作　　者：许晓燕[1] 陈文杰[1] 刘兴龙[1] Xu Xiaoyan Chen Wenjie Liu Xinglong(Institute of Microelectronics, Peking University, Beijing 100871, China)

机构地区：[1]北京大学微电子学研究院,北京100871

出　　处：《半导体技术》2016年第10期764-768,共5页Semiconductor Technology

基　　金：国家科技重大专项资助项目(2011ZX02013-006)

摘　　要：针对纳米PMOS器件超浅结工艺面临的硼扩散问题,开展了预非晶化与激光退火和碳共注入结合的超浅结实验,通过透射式电子显微镜(TEM),二次离子质谱(SIMS),扩展电阻法(SRP)等测试对超浅结特性进行评估。结果表明,采用激光退火和碳共注入的方式可有效抑制硼扩散和减小结深。锗预非晶化后5 ke V,1×10^(15)/cm^2条件下注入的硼在激光退火(波长532 nm、脉冲宽度小于20 ns、能量密度0.25 J/cm^2)中的再扩散量非常小,退火后结深较注入结深仅增加6 nm,但激活率仅为24%。相同的硼掺杂条件下采用碳的共注入,常规快速热退火下的结深较未注碳样品减小49%,而且实现了84%的硼激活率。在单项实验基础上,进一步将预非晶化和碳共注入技术应用于纳米尺度器件制作,实验制备了亚50 nm PMOS器件,器件在Vdd=-1.2 V时的电流开关比大于104,亚阈值斜率为100 m V/dec,漏致势垒降低(DIBL)值为104 m V/V。Aiming at the boron diffusion in ultra shallow junction technology of nano PMOS devices,the laser annealing and carbon co-implantation with pre-amorphization techniques were investigated. The characteristics of ultra shallow junction were evaluated by the techniques of transmission electron microscope（ TEM）, secondary ion mass spectroscopy（ SIMS） and spreading resistance profile（ SRP）.The results show that the boron diffusion is suppressed by laser annealing and carbon co-implantation,and the junction depth is also decreased. For samples with Ge pre-amorphization and an energy of 5 ke V boron ion implantation to a dose of 1 × 10^15/ cm^2,the junction depth after laser annealing（ wave length is 532 nm,pulse duration is less than 20 ns,and energy density is 0. 25 J / cm^2） is just 6 nm deeper than that of as-implanted and the boron activation rate is about 24%. Using carbon co-implantation under the same boron doping condition,the junction depth is 49% lower than that of the control one without carbon co-implantation and boron activation rate of 84% is obtained at conventional rapid thermal annealing. Based on above experimental results,the sub-50 nm PMOS devices are fabricated with the integration of pre-amorphization and carbon co-implantation into junction process flow. An on-off current ratio larger than 10-4 at Vdd=- 1. 2 V,subthreshold swing of 100 mV / dec,and drain-induced barrier lowering（ DIBL） value of 104 mV / V are observed in the fabricated devices.

关 键 词：预非晶化 激光退火 共注入 硼扩散 超浅结 

分 类 号：TN305.3[电子电信—物理电子学]