Vertical Profile Control in Ultrahigh-Aspect-Ratio Contact Hole Etching with 0.05-µm-Diameter Range
Vertical Profile Control in Ultrahigh-Aspect-Ratio Contact Hole Etching with 0.05-µm-Diameter Range
复制标题
直径范围为 0.05 µm 的超高深宽比接触孔蚀刻中的垂直轮廓控制
DOI：
10.1143/jjap.37.2337
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发表时间：
1998
影响因子：
1.5
通讯作者：
J. Kanamori
中科院分区：
文献类型：
--
作者：
N. Ikegami;A. Yabata;G. Liu;H. Uchida;N. Hirashita;J. Kanamori
采用偶极环型磁控反应离子刻蚀系统，在C4 F8/O2/Ar混合气体中实现了0.05 μ m级SiO2孔的垂直加工，孔的深宽比约为20。二次离子质谱研究的F和C的浓度分布的孔内沉积的聚合物在深度方向上显示，在这个系统中发生了非常少量的聚合物沉积。这表明，充满活力的物种达到孔底部具有良好的垂直度，即使在一个非常精细的功能。相比之下，CHF 3/CO工艺（锥形形状）导致侧壁上的极厚的聚合物和非晶区，这表明存在粘附到侧壁的高能物质。高能物种撞击到侧壁上的影响和聚合物沉积产生的保护已被讨论的蚀刻形状和F/C深度分布。垂直入射到孔的高能物质的结论是实现垂直剖面的一个重要因素。
Vertical processing of 0.05-µm-class SiO2 holes with an aspect ratio around 20 was realized using a dipole-ring-type magnetron reactive-ion-etching system in a mixture of C4F8/O2/Ar gas. Secondary ion mass spectrometric study of the F and C concentration profiles of the polymer deposited inside the holes in the depth direction revealed that a very small amount of polymer deposition occurred in this system. This indicates that energetic species reached the hole bottoms with excellent verticality, even in an extremely fine feature. In contrast, the CHF3/CO process (tapered shape) resulted in an extremely thick polymer and carbonized region on the sidewalls, suggesting the presence of energetic species sticking to the sidewalls. The effects of energetic species impinging onto the sidewalls and the protection resulting from polymer deposition have been discussed in terms of the etched shape and F/C depth profile. Vertical incidence of the energetic species into the holes is concluded to be a significant factor in realizing a vertical profile.