原子层淀积 Al2O3薄膜的热稳定性研究

以Al（CH3）3和H2O为反应源，在270℃下用原子层淀积（ALD）技术在Si衬底上生长了Al2O3薄膜．采用X射线衍射（XRD）、X射线光电子能谱（XPS）、原子力显微镜（AFM）和傅立叶变换红外光谱（FTIR）等分析手段对Al2O3薄膜的热稳定性进行了研究．结果表明刚淀积的薄膜中含有少量A-OH基团，高温退火后，Al-OH基团几乎消失，这归因于Al-OH基团之间发生反应而脱水．退火后的薄膜中O和Al元素的相对比例（1．52）比退火前的（1．57）更接近化学计量比的Al2O3．FTIR分析表明，在刚淀积的Al2O3中有少量的-CH3存在，CH3含量会随热处理温度的升高而减少．此外，在高温快速热退火后，Al2O3薄膜的表面平均粗糙度（RMS）明显改善，900℃热退火后其RMS达到1．15nm．     

阳极氧化铝的原子层淀积封孔研究

制备了多孔阳极氧化铝,利用原子层淀积技术对其封孔,借助场发射扫描电镜(SEM)分析了样品的表面及剖面形貌,对样品进行染色处理,利用酸性点滴试验测试样品抗腐蚀性能。结果表明:阳极氧化处理形成大孔径约为16 nm的多孔膜,多孔膜在循环50次的原子层淀积下能实现表面封孔而内部有空结构;经封孔后的样品抗染色及抗腐蚀能力增强。     

快速热退火对原子层淀积铂纳米颗粒的影响

以（MeCp）Pt（CH3）3和O₂为反应源,采用原子层淀积（ALD）技术在A1₂O₃衬底上制备Pt纳米颗粒,研究了在氮气中快速热退火对Pt纳米颗粒的特性的影响。结果表明,随着退火温度从700℃升高到900℃,Pt纳米颗粒尺寸逐渐增大,颗粒之间分离愈加清晰,形貌趋向球形,但颗粒密度稍有降低。随着在800℃退火时间从15 s增加到60 s,Pt纳米颗粒的尺寸逐渐增大,尺寸分布变得更加弥散,颗粒的密度逐渐降低;其中退火15 s后的Pt纳米颗粒密度高（9.29×10cm-2）、分布均匀、分离清晰。900℃退火后在Pt纳米颗粒中出现部分氧化态的Pt原子,其原因可能是在高温下Pt纳米颗粒与A1₂O₃薄膜之间发生了界面化学反应。     

卤素原子在化学气相淀积金刚石薄膜过程中的作用

根据非平衡热力学耦合模型计算得到了碳氢氟和碳氢氯体低压金刚石生长的非平衡定态相图，计算与大量实验事实符合良好。     

等离子增强化学气相淀积硅化钛薄膜的特性

本文以四氯化钛（ＴｉＣｌ４）和硅烷（ＳｉＨ４）为源物质，采用等离子增强化学气相淀积（ＰＥＣＶＤ）工艺结合常规热退火制备了优良的ＴｉＳｉ２薄膜。研究了淀积和退火条件对薄膜性质的影响。用四探针检测了退火前后薄膜的薄层电阻，用俄歇电子能谱（ＡＥＳ）和Ｘ射线衍射分析了薄膜的化学组成和晶体结构。     

集成电路薄膜工艺的新进展--化学液相淀积

介绍了化学液相淀积法制备氧化物薄膜的工艺过程及其在集成电路生产中的应用，并报道了一些最新研究成果。     

Atomic layer deposition of ferromagnetic cobalt doped titanium oxide thin films

TiO₂ thin films doped or mixed with cobalt oxide were grown by atomic layer deposition using titanium tetramethoxide and cobalt(III)acetylacetonate as metal precursors. The films could be deposited using both O₃ and H₂O as oxygen precursors. The films grown using water exhibited considerably smoother surface than those grown with ozone. The TiO₂:Co films with Co/(Co + Ti) cation ratio ranging from 0.01 to 0.30 were crystallized by annealing at 650 °C, possessing mixed phase composition comprising rutile and anatase and, additionally, CoTiO₃ or CoTi₂O₅. The annealed films demonstrated magnetic response expressed by magnetization curves with certain hysteresis and coercive fields.     

The uniformity of Al distribution in aluminum-doped zinc oxide films grown by atomic layer deposition

We investigated the aluminum distribution in aluminum-doped zinc oxide films grown by atomic layer deposition. Surface morphology, structure, composition and electrical properties of obtained films were studied. For the aluminum content less than 2 at.%, a periodicity of Al distribution along the layer depth was observed. This periodicity diminished significantly after annealing the samples in nitrogen atmosphere at 300 °C. For the Al content higher than 2 at.%, its distribution in ZnO:Al films was uniform within the depth measurement accuracy of ∼5-10 nm.     

原子层沉积技术及其在半导体中的应用

首先简述原子层沉积（ALD）技术的发展背景，通过分析ALD的互补性和自限制性等工艺基础，介绍了它在膜层的均匀性、保形性以及膜厚控制能力等方面的优势，着重列举ALD在半导体互连技术、高k电介质等方面的应用。同时指出了目前ALD工艺中存在的主要问题。     

Atomic layer deposition of Ru films from bis(2,5-dimethylpyrrolyl)ruthenium and oxygen

Ru thin films were grown on hydrogen terminated Si, SiO₂, Al₂O₃, HfO₂, and TiO₂ surfaces by atomic layer deposition from bis(2,5-dimethylpyrrolyl)ruthenium precursor and oxygen. The 4-20 nm thick films on these surfaces consisted of nanocrystalline hexagonal metallic ruthenium, regardless of the deposition temperature. At the lowest temperatures examined, 250-255 °C, the growth of the Ru films was favored on silicon, compared to the growth on Al₂O₃, TiO₂ and HfO₂. At higher temperatures the nucleation and growth of Ru became enhanced in particular on HfO₂, compared to the process on silicon. At 320-325 °C, no growth occurred on Si-H and SiO₂-covered silicon. Resistivity values down to 18 μΩ·cm were obtained for ca. 10 nm thick Ru films.     

Monocrystalline zinc oxide films grown by atomic layer deposition

In the present work we report on the monocrystalline growth of (00.1) ZnO films on GaN template by the Atomic Layer Deposition technique. The ZnO films were obtained at temperature of 300 °C using dietylzinc (DEZn) as a zinc precursor and deionized water as an oxygen precursor. High resolution X-ray diffraction analysis proves that ZnO layers are monocrystalline with rocking curve FWHM of the 00.2 peak equals to 0.07°. Low temperature photoluminescence shows a sharp and bright excitonic line with FWHM of 13 meV.     

Electrical properties of quaternary HfAlTiO thin films grown by atomic layer deposition

Quaternary alloyed HfAlTiO thin (~ 4-5 nm) films in the wide range of Ti content have been grown on Si substrates by Atomic Layer Deposition technique, and the effect of both the film composition and the interfacial reactions on the electrical properties of HfAlTiO films is investigated. It is shown that depending on the Ti content, the permittivity and the leakage current density I_leak in HfAlTiO films vary in the range k = 18 ÷ 28 and 0.01-2.4 A cm^− 2, respectively. The incorporation of ultra thin SiN interlayer in Al/HfAlTiO/SiN/Si stack gives rise to the sharp (× 10³) decrease of the I_leak ~ 6 · 10^− 5 A/cm² at the expense of the rather low capacitance equivalent thickness ~ 0.9 nm.     

Atomic layer deposition and characterization of biocompatible hydroxyapatite thin films

Atomic layer deposition (ALD) was used to produce hydroxyapatite from Ca(thd)₂ (thd = 2,2,6,6-tetramethyl-3,5-heptanedionato) and (CH₃O)₃PO onto Si(100) and Corning (0211). Film crystallinity, stoichiometry, possible impurities and surface morphology were determined. The as-deposited films contained significant amounts of carbonate impurities however, annealing at moist N₂ flow reduced the carbonate content even at 400 °C. The as-deposited Ca-P-O films were amorphous but rapid thermal annealing promoted the formation of the hydroxyapatite phase. Mouse MC 3T3-E1 cells were used for the cell culture experiments. According to the bioactivity studies cell proliferation was enhanced on as-deposited ALD-grown Ca-P-O films and greatly enhanced on films annealed at 500 °C in comparison with reference cells on borosilicate glass or cell culture polystyrene.     

Atomic layer deposition of palladium films on Al2O3 surfaces

We examined the atomic layer deposition (ALD) of Pd films using sequential exposures of Pd(II) hexafluoroacetylacetonate (Pd(hfac)₂) and formalin and discovered that formalin enables the efficient nucleation of Pd ALD on Al₂O₃. In situ quartz crystal microbalance measurements revealed that the Pd nucleation is hampered by the relatively slow reaction of the adsorbed Pd(hfac)₂ species, but is accelerated using larger initial Pd(hfac)₂ and formalin exposures. Pd nucleation proceeds via coalescence of islands and leaves hfac contamination at the Al₂O₃ interface. Pd films were deposited on the thermal oxide of silicon, glass and mesoporous anodic alumina following the ALD of a thin Al₂O₃ seed layer and analyzed using a variety of techniques. We measured a Pd ALD growth rate of 0.2 Å/cycle following a nucleation period of slower growth. The deposited films are cubic Pd with a roughness of 4.2 nm and a resistivity of 11 μΩ cm at 42 nm thickness. Using this method, Pd deposits conformally on the inside of mesoporous anodic alumina membranes with aspect ratio ∼1500 yielding promising hydrogen sensors.     

Electrical resistivity of Ti-Zn mixed oxide thin films deposited by atomic layer deposition

Ti-Zn mixed oxide thin films, with thickness less than 50 nm, were grown with atomic layer deposition (ALD) technique at low temperature (90 °C) varying the composition. ALD is a powerful chemical technique to deposit thin films with thickness of few atomic layers. ALD oxide material growth is achieved by dosing sequentially the metal precursor and the oxidizing agent. Thanks to ALD nature of layer by layer growth it was possible to realize mixed metal, Ti and Zn, oxide thin films with controlled composition, simply by changing the number of cycles of each metal oxide layer. Structural and electrical properties of the prepared thin films were studied as a function of their composition. Synchrotron radiation X-ray diffraction technique was used to follow thin film crystallization during sample annealing, performed in situ. It was observed that the onset temperature of crystallization raises with Ti content, and sample structure was Zn₂TiO4 phase. Electrical resistivity measurements were performed on crystalline samples, annealed at 600 °C, revealing an increase in resistivity with Ti content.     

Characterizations of NbAlO thin films grown by atomic layer deposition

Niobium-aluminate (NbAlO) thin films have been prepared on silicon (100) with different Nb₂O₅:Al₂O₃ growth cycle ratio by atomic layer deposition (ALD) technology. The structural, chemical and optical properties of NbAlO thin films are investigated using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and spectroscopic ellipsometry (SE). The results show that all the obtained NbAlO films are amorphous and fully oxidized. It is also found that the proportion of components in the NbAlO film can be well-controlled by varying the ALD growth cycles of the independent oxides. Furthermore, the refraction index of the prepared films is observed to increase with an increase of the concentration of Nb in the mixtures.