VLSI用低介电常数含氟碳膜研究

用等离子体增强化学气相沉积(PECVD)法制备了不同工艺条件下的含氟碳膜。测量了薄膜的厚度和介电常数,并用傅立叶红外光谱分析了薄膜化学结构,发现薄膜成分和介电性与沉积工艺密切相关,对薄膜的SEM分析表明所得薄膜均匀致密。控制适当的工艺条件,可沉积理想的超大规模集成电路(VLSI)用钝化膜。     

Effects of nitrogen content on structure and electrical properties of nitrogen-doped fluorinated diamond-like carbon films

Nitrogen-doped fluorinated diamond-like carbon (FN-DLC) films were prepared on single crystal silicon substrate by radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) under different deposited conditions with CF₄, CH₄ and nitrogen as source gases. The influence of nitrogen content on the structure and electrical properties of the films was studied. The films were investigated in terms of surface morphology, microstructure, chemical composition and electrical properties. Atomic force microscopy (AFM) results revealed that the surface morphology of the films became smooth due to doping nitrogen. Fourier transform infrared absorption spectrometry (FTIR) results showed that amouts of C=N and C

N bonds increased gradually with increasing nitrogen partial pressure r (r=p(N₂)/p(N₂+CF₄+CH₄)). Gaussian fit results of C 1s and N 1s in X-ray photoelectron spectra (XPS) showed that the incorporation of nitrogen presented mainly in the forms of β-C₃N₄ and a-CN_x (x=1, 2, 3) in the films. The current?voltage (I?V) measurement results showed that the electrical conductivity of the films increased with increasing nitrogen content.     

a-C:F:H films prepared by PECVD

Fluorinated amorphous hydrogenated a-C:F:H carbon thin films were deposited using radio frequency plasma enhanced chemical vapor deposition(RF-PECVD) reactor with CF4 and CH4 as source gases and were annealed in a N2 atmosphere. The properties of these films were evaluated by FTIR spectrometry, UV-VIS spectrophotometry and single-wavelength spectroscopic ellipsometry. A correspondence relativity connection between the deposition rate and technology was found. The chemical bonding structures and the content of CHx and CFx in the films are transformed and the optical band gap decreases monotonically with increasing temperature after annealing.The dielectric constant is increased with decreasing content of F in the films and the optical band gap is decreased with decreasing the content of H in the film.     

a-C:F:H薄膜的化学键结构

使用CF4和CH4为源气体,利用射频等离子体增强化学气相沉积法,制备了a-C:F:H薄膜样品.采用拉曼光谱仪、傅里叶变换红外光谱仪、X射线光电子能谱仪(XPS)对薄膜的结构进行了测试和分析.研究发现:该膜呈空间网状结构,膜内碳与氟、氢的结合主要以sp3形式存在,而sp2形式的含量相对较少;在薄膜内主要含有C-Fx(x=1,2,3)、C-C、C-H2、C-H3等以及不饱和C=C化学键;同时,薄膜中C-C-F键的含量比C-C-F2键的含量要高.在不同功率下沉积的薄膜,其化学键结构明显不同.     

PECVD法制备低介电常数含氟碳膜研究

采用PECVD法制备了低介电常数薄膜a-C：F，研究了薄膜沉积速率与温度及射频功率的关系，测量了不同沉积条件下薄膜的介电常数，并用FTIR分析了薄膜的化学结构及成分，发现薄膜沉积速率与沉积条件密切相关，其介电性与其化学结构以及沉积条件密切相关。     

复合正极材料xLiFePO_4·yLi_3V_2(PO_4)_3/C的合成及其电化学性能

以聚吡咯(PVP K60)为表面活性剂和碳源,采用流变相法合成了x Li Fe PO4·y Li3V2(PO4)3/C正极材料样品。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)对样品形貌和结构进行了测试;采用电池测试仪和电化学工作站对样品电化学性能进行了测试,分析了不同复合比(x:y)对其结构和电化学性能的影响。研究表明:复合材料中存在两相复合与元素掺杂两种效应;当复合比为5∶1时材料的电化学性能最优,在0.1和10 C倍率下放电容量分别达到162.7和104.6 m Ah·g-1,且具有良好的循环稳定性。     

真空退火对a-C:F:H薄膜的结构与光学带隙的影响

使用CF4和CH4为源气体,利用射频等离子体增强化学气相沉积(RF-PECVD)法制备了掺氟非晶碳(a-C:F:H)薄膜,并在N2气氛中进行了不同温度的退火.用原子力显微镜(AFM)观察了薄膜在退火前后表面形貌的变化,发现退火后薄膜表面变得平坦,疏松.用紫外-可见光透射光谱(UV-VIS)并结合傅里叶变换红外光谱(FTIR)和喇曼(Raman)光谱对薄膜进行了分析,获得了薄膜化学键结构和光学带隙的变化情况;发现薄膜的化学键结构和光学带隙与真空退火密切相关,高温退火后薄膜化学键结构:CHx(x=1,2,3下同)、F-芳基、CF2和CF等基团的含量改变;薄膜的光学带隙决定于CHx、退火后CHx含量减少导致薄膜光学带隙的减小.     

氮化铜薄膜的研究

氮化铜(Cu_3N)薄膜是一种新型的电、光学材料,它具有典型的反三氧化铼结构,由于Cu原子没有很好地占据(111)晶格面的紧密位置.在薄膜中掺杂之后,薄膜的电、光学性质会发生显著变化.Cu_3N在较低温度下会分解为Cu和N_2.介绍了Cu_3N的制备方法,总结了该膜制备方法和工艺参数对薄膜结构的影响,分析了在不同N_2分压下薄膜由(111)晶面转向(100)晶面择优生长和薄膜定向生长的原因,讨论了薄膜的电学、光学、热学等物理性质及其在相关方面的应用,并对该膜的物理性质与结构之间的关系作了简要分析.     

a-C:F薄膜的工艺及热稳定性研究

以CF4和CH4为源气体,用PECVD法制备了不同沉积条件下的a-C:F薄膜,测量了薄膜的厚度,研究了薄膜沉积速率和沉积工艺的关系,用傅立叶变换红外谱(FTIR)分析了薄膜的化学键结构,用扫描电镜和原子力显微镜分析了薄膜表面形貌,对薄膜在真空中进行了退火,研究了薄膜的热稳定性.实验表明,沉积速率在5～8 nm/min之间,薄膜表面平整、致密,在300℃内有较好的热稳定性.     

a-C∶F∶H films prepared by PECVD

1　INTRODUCTIONRecentadvancesinultralargescaleintegrationdevices(ULSI)haveledtoaneedfornewintercon netionsmaterialswithlowresistivityandinterlayermaterialswithlowdielectricconstanttoreducetheinterconnetiondelay ,interfere ,noiseandwastagecausedbyparasiticcapacitance .ReplacingAlintradi tionalAl/SiO2 systemwithCu ,ithasreachedaunanimousagreement .MaterialsunderresearchtoreplaceSiO2 mainlycontainPTFE ,SiOF ,F PIanda C∶F∶H .PTFE(κ≈2 .0 )andSiOF(κ≈3.0～3.5 )havelowdielectric…