表面光电压技术在Si外延过程中的应用  

SPV Application in Silicon Epitaxial Process

作　　者：赵丽霞[1,2] 张鹤鸣[2] 陈秉克[1] 

机构地区：[1]河北普兴电子科技股份有限公司,石家庄050200 [2]西安电子科技大学微电子学院,西安710071

出　　处：《微纳电子技术》2009年第6期366-370,共5页Micronanoelectronic Technology

摘　　要：介绍了用表面光电压(SPV)法测试少数载流子的扩散长度、少子寿命和体Fe含量的基本原理及其计算方法,分析了三种常见外延结构中少子扩散长度的测试方法及其影响因素,得出了用于表面光电压测试的外延片及衬底片应满足的条件。提出了在外延工艺前后,用SPV法测试同一p型控片中少子的扩散长度和体Fe含量,对比前后值的大小来监测Si外延工艺过程中的沾污情况。分别给出了衬底片、石墨基座、HCl、SiHCl3、外延腔体等5种Si外延过程中最常见沾污源的监控和识别流程,特别以平板式外延腔体为例,具体说明了识别及排除Fe沾污所运行的工艺程序,并对Fe沾污的测试结果进行了分析,确定了Fe沾污的来源。The fundamental principle and calculation method to measure the minority carrier diffusion length, lifetime and bulk Fe content by surface photovoltage method were introduced. The measurement methods and interferential factors of three familiar epitaxial types were analyzed. The sample conditions of epitaxial wafers and substrates for SPV were got. The method was put forward using SPV to measure the same p-type monitor wafer before and after epitaxial process and compare the change of the diffusion length and bulk Fe content to monitor the epitaxial process. The monitor and identification procedures of five familiar contaminations, including the substrate, susceptor, HCl, SiHCl3 and epitaxial chamber, were given respectively. A pancake reactor was given as an example to illuminate how to identify and remove the Fe contamination source. Using this approach, the contamination source can be identified very quickly and accurately.

关 键 词：表面光电压 少数载流子 扩散长度 寿命 外延 衬底 

分 类 号：TN304.12[电子电信—物理电子学] TN304.054