Plasma etching selectivity of ZrO2 to Si in BCl3/Cl2 plasmas
Plasma etching selectivity of ZrO2 to Si in BCl3/Cl2 plasmas
复制标题
BCl3/Cl2 等离子体中 ZrO2 对 Si 的等离子体蚀刻选择性
DOI：
10.1116/1.1615975
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Jane P. Chang
中科院分区：
文献类型：
--
作者：
Lin Sha;Jane P. Chang
为了提高ZrO 2的刻蚀选择性，一种有前途的高k电介质材料在硅上，BCl 3被添加到Cl 2等离子体，以提高ZrO 2的刻蚀速率，同时抑制硅的刻蚀速率。利用朗缪尔探针、发射光谱和四极质谱对BCl 3/Cl 2等离子体中的电子温度、离子密度和气相组成进行了表征。最大的ZrO 2蚀刻速率与在BCl 3/Cl 2等离子体中BCl 3为40%时获得的最高离子密度相一致。在蚀刻ZrO 2中，氧作为硼-氧-氯化合物被去除，与其作为ClO+在纯Cl 2等离子体中的去除相反。通过X射线光电子能谱证实了形成B-Si键的硅的硼钝化。在纯BCl 3等离子体中刻蚀ZrO 2和Si的阈值能量分别为21和28 eV。在离子能量为75 eV时，ZrO 2和Si之间的蚀刻选择性在纯Cl 2等离子体中为1.01，在纯BCl 3等离子体中为1.5。刻蚀选择性得到了提高。
To improve the etching selectivity of ZrO2, a promising high-k dielectric material on silicon, BCl3 was added to a Cl2 plasma to enhance the ZrO2 etch rate while suppressing the silicon etch rate. The electron temperature, ion density, and gas-phase composition in BCl3/Cl2 plasmas were characterized by Langmuir probe, optical emission spectroscopy, and quadrupole mass spectrometry. The maximum ZrO2 etch rate coincides with the highest ion density obtained at 40% of BCl3 in BCl3/Cl2 plasmas. In etching ZrO2, oxygen was removed as boron-oxygen-chlorine compounds, in contrast to its removal as ClO+ in a pure Cl2 plasma. Boron passivation of silicon forming B–Si bonds was confirmed by x-ray photoelectron spectroscopy. The threshold energies for etching ZrO2 and Si in pure BCl3 plasmas were determined to be 21 and 28 eV, respectively. At an ion energy of 75 eV, the etching selectivity between ZrO2 and Si was ∼0.01 in a pure Cl2 plasma to ∼1.5 in a pure BCl3 plasma. The etching selectivity was increased to be g...