晶圆热处理过程中滑移缺陷机理及抑制方法研究

Effect and improving methods of induced slip defects during silicon wafer thermal process

集成电路生产成本进一步降低及生产效率不断提升的要求下,不同领域采用大晶圆已成为一种趋势,与此同时,器件尺寸不断减小及工艺技术发展大背景下,对晶圆及硅基器件的性能、质量要求也越来越高。随着晶圆尺寸增大,在使用立式热氧化扩散设备进行工艺过程中受到重力和应力影响也随之大幅提升,从而导致热处理特别是超过1000℃的高温工艺更易产生或放大晶体内部缺陷,极易造成器件失效产品报废,其中最为明显和影响最大的一类是滑移缺陷。因此,高温处理过程中减少或避免产生滑移缺陷从而提升器件性能、提高产品良率变得愈加重要,对立式氧化扩散设备腔室结构特别是晶圆支撑设计改进提出了更高要求。关于晶圆滑移的产生和抑制的文献报道很多,随着量测技术不断发展,早期理论和经验也在不断更新,本论文系统性总结分析了晶圆热处理过程中缺陷产生的机理及影响因素,基于最新研究进展和实践经验,提出了立式氧化扩散设备晶圆滑移缺陷的抑制方法。

In order to reduce IC costs and increase productivity,it has become a trend to employ large size wafers.Meanwhile,as the size of the device continues to shrink,the whole industry puts forward higher requirements for the performance and quality of silicon chips and silicon based devices.Increased wafer diameter leads to increases in both gravitational stresses and thermal stresses,and slip dislocations is caused in the process of high temperature heat treatment,especially process exceeding 1000℃.However,the generation of slip defect is harmful and affects the performance of semiconductor devices and may cause device failure.Therefore,it becomes important to reduce the occurrence of slip during heat treatment.And it has higher requirements for the wafer support structure of vertical oxidation diffusion equipment.There are many literature reports on the generation and inhibition of wafer slip,but few systematic summaries.Moreover,measurement technology and early theories are also being updated iteratively.In this review,we describe the recent progress in the field of silicon wafer slip and discuss the effect and improving methods of induced slip defects during silicon wafer thermal process.Finally,we propose an optimization direction for the suppression method of wafer slip in vertical diffusion furnace based on the current progress.