重掺衬底/轻掺硅外延层制备工艺研究  

Research on Preparation Process of Lightly Doped Silicon Epitaxial Layer/Heavy Doped Substrate

作　　者：刘云 李明达 LIU Yun;LI Mingda(CETC JinghuaSemiconductor Materials Co.,Ltd.,Tianjin 300220,China)

机构地区：[1]中电晶华(天津)半导体材料有限公司,天津300220

出　　处：《天津科技》2021年第2期28-31,35,共5页Tianjin Science & Technology

摘　　要：轻掺硅外延层/重掺衬底的过渡层结构、厚度均匀性、电阻率均匀性等关键参数与所制器件的性能密切相关。通常基于重掺衬底的轻掺硅外延层,电阻率比厚度数值至少会低一个数量级,可以有足够的反应时间攀升到稳定轻掺态。但在光电探测应用领域,所需外延层电阻率高于厚度数值2倍以上,并且要求电阻率、厚度参数控制精确,均匀性好、过渡层窄,晶格完整性好。传统外延工艺中电阻率受自掺杂影响,爬升速率缓慢,均匀性及过渡层形貌始终不能达到预期目标。基于外延掺杂机理,通过设计本征层预覆盖、基座包硅等多种手段,可有效抑制系统自掺杂干扰,实现了光电探测级高均匀性外延层的研制能力。The key parameters of the lightly doped silicon epitaxial layer/heavy doped substrate such as the transition region structure,thickness uniformity and resistivity uniformity are closely related to the performance of the manufactured device.Usually based on a lightly doped silicon epitaxial layer on a heavily doped substrate,the resistivity is at least an order of magnitude lower than the thickness value,and there is enough reaction time to climb to a stable lightly doped state.However,in the field of photodetection applications,the resistivity of the epitaxial layer is more than 2 times higher than the thickness value,and the resistivity and thickness parameters are controlled accurately,with good uniformity,narrow transition region and good lattice integrity.In the traditional epitaxial process,the resistivity is affected by the self-doping,the climbing rate is slow,and the uniformity and the morphology of the transition region cannot reach the expected goals.Based on the epitaxial doping mechanism,the self-doping interference of the system can be effectively suppressed by designing the intrinsic layer pre-covering and the silicon-coated susceptor,and the development ability of the photoelectric detection level high uniformity epitaxial layer is realized.

关 键 词：硅外延 轻掺 均匀性 过渡层 

分 类 号：TN304.054[电子电信—物理电子学]