掺硼纳米晶粒多晶Si薄膜的结构特征与电学特性  

Structural Characteristics and Electrical Properties of the Boron-doped Nanograin Polysilicon Thin Films

作　　者：彭英才[1] 康建波[1] 马蕾[1] 张雷[1] 王侠[1] 范志东[1] 

机构地区：[1]河北大学电子信息工程学院

出　　处：《人工晶体学报》2008年第2期471-474,465,共5页Journal of Synthetic Crystals

基　　金：中国科学院半导体研究所半导体材料科学重点实验室开放课题

摘　　要：采用低压化学气相沉积(LPCVD)工艺,以SiH4作为反应气体源和B2H6作为硼(B)掺杂剂,在单晶Si或石英表面上,通过原位掺杂制备了掺B的纳米晶粒多晶Si(nc-poly-Si(B))薄膜。利用扫描电子显微镜(SEM)、原子力显微镜(AFM)和拉曼光谱等手段,检测和分析了沉积膜层的表面形貌、晶粒尺寸和密度分布等结构特征。结果表明,在典型工艺条件下,获得了晶粒尺寸为大约15 nm和密度分布为大约9×1010cm-2的nc-poly-Si(B)薄膜。样品经退火处理后,Si晶粒尺寸变大,排列更加有序,而且电导特性明显改善。利用常规四探针法测量了样品的薄层电阻,并讨论了B掺杂浓度和退火温度对薄膜电学性质的影响。The boron-doped nanograin polysilicon films （nc-poly-Si （B）） are fabricated on crystal Si or quartz substrates by low pressure chemical vapor depotition （LPCVD） via in situ doping method. Sill4 and B2H6 are used as reactive gas and doping soruce, respectively. The microstructure of the asdeposited and annealed thin films are demonstrated by scanning electronic microscopy （SEM）, atomic force microscopy （AFM） and Raman scattering spectroscopy. The results indicate that the size and the density of Si nanograins fabricated under typical experimental conditions are about 15 nm and 9.0 × 10^10 cm2 , respectively. After thermal annealing, the sizes of Si grains becom bigger, arrange is more orderliness, and conductance properties of the films are also significantly improved. The sheet resistances of the nc-poly-Si （B） films are measured by four probe method, and the effects of B doping concentration and thermal annealing on electrical properties are also discussed.

关 键 词：LPCVD nc-poly-Si(B)薄膜 结构特征 热退火 电学性质 

分 类 号：O78[理学—晶体学]