Structure of low dielectric constant to extreme low dielectric constant SiCOH films: Fourier transform infrared spectroscopy characterization
Structure of low dielectric constant to extreme low dielectric constant SiCOH films: Fourier transform infrared spectroscopy characterization
复制标题
DOI：
10.1063/1.1618358
复制
发表时间：
2003-11-15
影响因子：
3.2
通讯作者：
Neumayer, DA
中科院分区：
文献类型：
--
作者：
Grill, A;Neumayer, DA
以四甲基环四硅氧烷(TMCTS)和有机前驱体为原料，采用等离子体增强化学气相沉积(PECVD)法制备了由Si、C、O和H(SiCOH)组成的碳掺杂氧化物介电材料。通过测定薄膜的元素组成和傅里叶变换红外光谱对薄膜进行了分析，并对吸收峰解卷积。分析表明，TMCTS的PECVD得到了高度交联的网络SiCOH薄膜。TMCTS的解离似乎主导了沉积化学，这从众多的成键环境和线性链和支链的形成中可见一斑。TMCTS环通过Si-Si、Si-CH2-Si、Si-O-Si和Si-CH2-O-Si部分发生广泛的交联。由TMCTS和有机前驱体的混合物沉积的薄膜中含有碳氢化合物碎片。这种结合很可能是通过TMCTS的有机前体和Si-H键的反应进行的。由TMCTS和有机前驱体沉积的SiCOH薄膜由于结合的有机成分的碎裂和损失，导致薄膜中的碳和氢的大量损失。退火后薄膜的Si-O-Si不对称伸缩带的反卷积表明，与仅由TMCTS沉积的薄膜相比，由TMCTS和有机前驱体混合沉积的SiCOH薄膜中存在较大比例的笼状结构和较小的网状(高度交联)结构。在热处理过程中，挥发性碳氢化合物碎片的演化导致了纳米孔的形成，从而使薄膜的介电常数降低到极低的-k值。(C)2003年美国物理研究所。
Carbon doped oxide dielectrics comprised of Si, C, O, and H (SiCOH) have been prepared by plasma enhanced chemical vapor deposition (PECVD) from mixtures of tetramethylcyclotetrasiloxane (TMCTS) and an organic precursor. The films have been analyzed by determining their elemental composition and by Fourier transform infrared spectroscopy with deconvolution of the absorption peaks. The analysis has shown that PECVD of TMCTS produces a highly crosslinked networked SiCOH film. Dissociation of TMCTS appears to dominate the deposition chemistry as evidenced by the multitude of bonding environments and formation of linear chains and branches. Extensive crosslinking of TMCTS rings occurs through Si-Si, Si-CH2-Si, Si-O-Si, and Si-CH2-O-Si moieties. The films deposited from mixtures of TMCTS and organic precursor incorporate hydrocarbon fragments into the films. This incorporation occurs most probably through the reaction of the organic precursor and the Si-H bonds of TMCTS. Annealing the SiCOH films deposited from TMCTS and organic precursor results in a large loss of carbon and hydrogen from the films resulting from the fragmentation and loss of the incorporated organic component. The deconvolution of the Si-O-Si asymmetric stretching band of the annealed films shows the existence of a larger fraction of a cage structure and a correspondingly smaller fraction of a networked (highly crosslinked) structure in the SiCOH films deposited from mixtures of TMCTS with organic precursor relative to the films deposited from TMCTS only. The evolution of the volatile hydrocarbon fragments during annealing results in the formation of nanopores and subsequent reduction of the dielectric constants of the films to extreme low-k values. (C) 2003 American Institute of Physics.