Highly selective SiO2 etching over Si3N4 using a cyclic process with BCl3 and fluorocarbon gas chemistries

被引:7
|
作者
Matsui, Miyako [1 ]
Kuwahara, Kenichi [2 ]
机构
[1] Hitachi Ltd, Res & Dev Grp, Kokubunji, Tokyo 1858601, Japan
[2] Hitachi High Technol Corp, Kudamatsu, Yamaguchi 7440002, Japan
关键词
SURFACE-REACTION; PLASMA; SILICON; SYSTEM; HFO2;
D O I
10.7567/JJAP.57.06JB01
中图分类号
O59 [应用物理学];
学科分类号
摘要
A cyclic process for highly selective SiO2 etching with atomic-scale precision over Si3N4 was developed by using BCl3 and fluorocarbon gas chemistries. This process consists of two alternately performed steps: a deposition step using BCl3-mixed-gas plasma and an etching step using CF4/Ar mixed-gas plasma. The mechanism of the cyclic process was investigated by analyzing the surface chemistry at each step. BClx, layers formed on both SiO2 and Si3N4 surfaces in the deposition step. Early in the etching step, the deposited BClx layers reacted with CFx radicals by forming CClx and 6F(x). Then, fluorocarbon films were deposited on both surfaces in the etching step. We found that the BClx layers formed in the deposition step enhanced the formation of the fluorocarbon films in the CF4 plasma etching step. In addition, because F radicals that radiated from the CF4 plasma reacted with B atoms while passing through the BClx layers, the BClx layers protected the Si3N4 surface from F-radical etching. The deposited layers, which contained the BClx, CClx, and CFX components, became thinner on SiO2 than on Si3N4, which promoted the Ion-assisted etching of SiO2. This is because the BClx component had a high reactivity with SiO2, and the CFx component was consumed by the etching reaction with SiO2. (c) 2018 The Japan Society of Applied Physics
引用
收藏
页数:6
相关论文
共 50 条
  • [1] Mechanism of highly selective SiO2 etching over Si3N4 using a cyclic process with BCl3 and fluorocarbon gas chemistries
    Matsui, Miyako
    Usui, Tatehito
    Kuwahara, Kenichi
    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A, 2020, 38 (02):
  • [2] Fluorocarbon based atomic layer etching of Si3N4 and etching selectivity of SiO2 over Si3N4
    Li, Chen
    Metzler, Dominik
    Lai, Chiukin Steven
    Hudson, Eric A.
    Oehrlein, Gottlieb S.
    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A, 2016, 34 (04):
  • [3] Mechanism of selective Si3N4 etching over SiO2 in hydrogen-containing fluorocarbon plasma
    Chen, Lele
    Xu, Linda
    Li, Dongxia
    Lin, Bill
    MICROELECTRONIC ENGINEERING, 2009, 86 (11) : 2354 - 2357
  • [4] SELECTIVE ISOTROPIC DRY ETCHING OF SI3N4 OVER SIO2
    SANDERS, FHM
    DIELEMAN, J
    PETERS, HJB
    SANDERS, JAM
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1982, 129 (11) : 2559 - 2561
  • [5] Selective SiO2-to-Si3N4 etching in inductively coupled fluorocarbon plasmas:: Angular dependence of SiO2 and Si3N4 etching rates
    Schaepkens, M
    Oehrlein, GS
    Hedlund, C
    Jonsson, LB
    Blom, HO
    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS, 1998, 16 (06): : 3281 - 3286
  • [6] SELECTIVE SPUTTER-ETCHING OF SIO2 AND SI3N4
    KUROGI, Y
    TAJIMA, M
    MORI, K
    SUGIBUCHI, K
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1977, 124 (08) : C284 - C284
  • [7] Role of CF2 in the etching of SiO2, Si3N4 and Si in fluorocarbon plasma
    Chen Lele
    Zhu Liang
    Xu Linda
    Li Dongxia
    Cai Hui
    Tod, Pao
    JOURNAL OF SEMICONDUCTORS, 2009, 30 (03)
  • [8] Role of CF2 in the etching of SiO2,Si3N4 and Si in fluorocarbon plasma
    陈乐乐
    朱亮
    徐昕睿
    李东霞
    蔡辉
    包大勇
    半导体学报, 2009, (03) : 30 - 34
  • [9] STUDIES ON THE MECHANISM OF SELECTIVE ISOTROPIC DRY ETCHING OF SI3N4 OVER SIO2
    SANDERS, FHM
    DIELEMAN, J
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1983, 130 (03) : C84 - C84
  • [10] Highly Selective Etching of SiO2 over Si3N4 and Si in Capacitively Coupled Plasma Employing C5HF7 Gas
    Miyawaki, Yudai
    Kondo, Yusuke
    Sekine, Makoto
    Ishikawa, Kenji
    Hayashi, Toshio
    Takeda, Keigo
    Kondo, Hiroki
    Yamazaki, Atsuyo
    Ito, Azumi
    Matsumoto, Hirokazu
    Hori, Masaru
    JAPANESE JOURNAL OF APPLIED PHYSICS, 2013, 52 (01)