37CrMnMo钢表面原子层沉积Al2O3超薄膜的防护性能

利用原子层沉积(ALD)技术在37CrMnMo钢表面沉积Al2 O3超薄膜,通过极化曲线、电化学阻抗谱以及形貌表征,分析了薄膜的致密性以及薄膜厚度对基底的防护效果.结果表明:超薄Al2 O3膜致密均匀,且薄膜孔隙率随其厚度的增加而降低;与合金钢基材相比,表面沉积150 nm厚Al2 O3薄膜的37CrMnMo钢,其腐蚀...     

Ni-W-GO-Al_2O_3复合镀层的制备及其耐磨耐蚀性能

首先采用纳米Al_2O_3颗粒对氧化石墨烯(GO)进行表面改性,然后利用脉冲电沉积技术在碳钢表面制备了Ni-W-GO-Al_2O_3复合镀层,采用扫描电镜、摩擦磨损试验机和电化学工作站等研究了复合镀层的形貌、组织结构及耐磨耐蚀性能。结果表明:Al_2O_3的加入抑制了GO团聚,有助于镀层组织均匀化;与单纯的Ni-W-GO镀层相比,Ni-W-GO-0.3Al_2O_3镀层表面平整、致密无裂纹,耐磨耐蚀性能最好;Al_2O_3添加量过低,起不到抑制GO团聚的效果;添加量过高,Al_2O_3发生自发团聚,形成大量裂纹,既降低镀层的耐蚀性,同时也降低耐磨性。     

HOPG上ALD沉积Al_2O_3介电薄膜的生长行为研究（英文）

采用原子层沉积(ALD)的方法,选择三甲基铝(TMA)和H_2O_2作为反应前驱体,在高定向热解石墨(HOPG)基体上沉积Al_2O_3。系统研究了反应温度和生长周次对Al_2O_3生长行为的影响。研究表明:受HOPG表面饱和成键的影响,Al_2O_3在衬底表面处形核困难,在生长初期主要表现为台阶处择优生长,其形态为线状结构。当沉积100周次Al_2O_3时,其中在沉积温度为50°C、150°C和200°C时呈现为纳米线状结构,而在100°C时呈现为非连续薄膜。随着生长周次的增加,不同温度下沉积态Al_2O_3都趋于形成连续薄膜,表明其生长行为发生了由三维岛状生长模式向二维平面生长模式的转变。分析认为,生长模式的转变是由纳米线状结构横向生长造成的;横向生长速率主要受生长温度影响。拉曼结果表明:沉积后的石墨烯层结构未受影响,可保留其原有的优越性能。     

Al_2O_3微粉添加量对镁合金微弧氧化膜特性影响

为了研究添加Al_2O_3微粉对AZ31A镁合金微弧氧化膜特性影响,在不同浓度Al_2O_3微粉氧化液中对其进行了微弧氧化处理。利用扫描电镜(SEM)观察了微弧氧化膜形貌,能谱仪(EDS)分析了膜层表面Ca、Mg、O、Al元素分布,X射线衍射仪(XRD)分析了相组成,测定了膜厚、硬度和氧化液中Al_2O_3表面电荷,讨论了改性机理。结果表明,加入Al_2O_3微粉后,氧化电压随Al_2O_3添加量增加先增加后降低;氧化膜表面孔洞数量和尺寸减小,膜层表面Ca元素分布逐渐减少,成膜效率降低,膜层致密度和表面疏松层硬度提高,氧化膜主要由MgO和MgO_4等相组成。     

不锈钢管内表面钝化膜ALD制备及抗结焦性能

采用原子层沉积(ALD)技术在SS316不锈钢管内壁制备了Al_2O_3、TiO_2和Ru钝化层,研究其对抗结焦性能影响。结果表明:所制备Al_2O_3钝化薄膜相结构为γ-Al_2O_3,TiO_2为锐钛矿结构,Ru为密排六方结构。钝化处理能够延长燃油循环系统工作时间,管内循环燃油在800℃保温过程中,Al_2O_3引起系统压降升高,而TiO_2对系统的压降略有降低。对比TiO_2和未钝化管的结焦形貌,TiO_2钝化处理有效降低了表面焦油滴的尺寸和数量,同时在TiO_2钝化管未发现丝状碳的产生,无定型碳的数量也有所降低,说明TiO_2钝化层有着优异的抗结焦能力。酒精超声清洗后,TiO_2和Ru钝化管胶质层完全脱落,说明其胶质层结构较为疏松或胶质层较薄;Al_2O_3和未钝化管胶质层只存在部分脱落,说明其胶质层和沥青质层结合力较好或有着较厚的胶质层。实验表明,TiO_2和Ru钝化层抗结焦性能优于Al_2O_3钝化层。     

粉末靶射频磁控溅射非晶Al_2O_3薄膜的制备与性能研究

采用粉末靶射频磁控溅射方法制备非晶Al_2O_3薄膜,分析了溅射工艺参数对Al_2O_3薄膜微观结构、表面形貌、光学性能的影响规律及机理,并探究其抗菌特性.研究结果表明:增加氧通量、降低溅射功率和缩短溅射时间均会减小非晶Al_2O_3薄膜颗粒度与粗糙度,同时也降低薄膜的沉积速率;并且,氧通量的增加和溅射时间的缩短均会使非晶Al_2O_3薄膜禁带宽度变宽(最大值可达4.21 e V)、透光率增大(超过90%);光照条件下非晶Al_2O_3薄膜24 h抗菌率最高可达98.6%,体现出了较好的光催化抗菌性.     

TiN/TiCN/Al2O3/TiN与TiN/TiCN/Al2O3/TiCNO多层涂层的组织性能比较

目的对比TiN/TiCN/Al_2O_3/TiN和TiN/TiCN/Al_2O_3/TiCNO两种多层涂层的组织性能。方法采用化学气相沉积(CVD)技术在硬质合金基体上沉积TiN/TiCN/Al_2O_3/TiN和TiN/TiCN/Al_2O_3/TiCNO两种多层涂层。通过X射线衍射仪(XRD)和扫描电子显微镜(SEM)分析涂层的物相和组织形貌,采用纳米力学测试系统测试涂层顶层的硬度和弹性模量,利用显微维氏硬度计和划痕仪分别测量涂层的显微硬度和结合强度,利用往复式多功能摩擦磨损试验机研究涂层的摩擦磨损性能。结果顶层TiN晶粒为柱状晶,顶层TiCNO晶粒呈细针状。与顶层TiN相比,顶层TiCNO硬度更大,抗塑性变形能力更强。与以TiN为顶层的多层涂层相比,以TiCNO为顶层的多层涂层表面粗糙度、摩擦系数较大,结合强度较低。当磨损只发生在顶层时,耐磨性取决于顶层涂层的性能,TiN/TiCN/Al_2O_3/TiN的磨损体积和磨损率为TiN/TiCN/Al_2O_3/TiCNO的1.2倍。当磨损进行到顶层与Al_2O_3层界面时,结合强度对耐磨性也有重要影响,TiN/TiCN/Al_2O_3/TiN的磨损体积和磨损率是TiN/TiCN/Al_2O_3/TiCNO的82%。结论与TiN/TiCN/Al_2O_3/TiN相比,TiN/TiCN/Al_2O_3/TiCNO的顶层TiCNO硬度较大,抗塑性变形能力强,其顶层耐磨性较好。改善TiN/TiCN/Al_2O_3/TiCNO多层涂层表面粗糙度和结合强度将进一步提高该涂层的摩擦磨损性能。     

Al-12.5％Si合金表面ZrO2溶胶改性PEO陶瓷层的形成机制

采用ZrO_2溶胶改性的等离子体电解氧化(PEO)技术在Al-12.5%Si合金表面制备Al_2O_3-ZrO_2陶瓷层,研究ZrO_2溶胶对PEO陶瓷层形成机制的影响。采用扫描电镜(SEM)、能谱仪(EDS)、X射线衍射仪(XRD)、红外光谱仪(FTIR)和激光粒度仪等研究了ZrO_2溶胶的微观组织结构、粒径及荷电性以及陶瓷层的微观形貌、成分及物相。结果表明:荷负电的ZrO_2溶胶粒径为50～60 nm,烧结后以四方相t-ZrO_2存在,含有少量m-ZrO_2。ZrO_2溶胶改性的PEO涂层较未改性的涂层均匀、致密,并且生长速率提高。由于ZrO_2溶胶吸附在基体表面形成凝胶层,凝胶层的高电阻使PEO初期更易产生火花放电,促进了Al_2O_3膜的形成。ZrO_2溶胶改性的PEO涂层由Al_2O_3、c-ZrO_2、t-ZrO_2和少量的SiO_2组成,而溶胶改性前SiO_2的含量较高。ZrO_2凝胶颗粒在等离子体放电产生的高温下进入放电通道,与电化学反应形成的Al_2O_3烧结形成Al_2O_3-ZrO_2复合陶瓷层。     

镁合金表面磁控溅射-微弧氧化制备Al_2O_3膜层的组织结构及性能

采用磁控溅射-微弧氧化的方法在镁合金表面制备了Al_2O_3膜层,随后采用X射线衍射分析(XRD)、扫描电镜(SEM)、能谱分析(EDX)等方法对微弧氧化膜层的相结构、截面形貌及膜层中的元素分布进行了分析,采用摩擦磨损和电化学腐蚀方法对膜层的耐磨耐腐蚀特性进行了测试。结果表明,通过先进行磁控溅射后进行微弧氧化的方式可以在镁合金表面获得Al_2O_3微弧氧化膜层。通过改变反应终止电压可控制微弧氧化膜层的厚度。当反应终止电压不高于510 V,膜层主要由铝和Al_2O_3组成。而当微弧氧化反应终止电压超过600 V后,铝膜层完全参与反应转变为微弧氧化膜层,膜层主要由Al_2O_3和MgO组成。Al_2O_3微弧氧化膜层的形成有助于提高镁合金表面的耐磨耐腐蚀性能。     

不同沉积温度下AZO透明导电薄膜的性能研究

以纯度为99.99%氧化锌铝(w(Zn O)=98.00wt%,w(Al_2O_3)=2.00wt%)陶瓷靶为原料,利用直流磁控溅射法在普通白玻璃衬底上制备铝掺杂氧化锌(AZO)薄膜。利用X射线衍射仪(XRD)、扫描电镜(SEM)、四点探针测试仪和紫外可见光分光光度计等对薄膜的形貌、结构及光电性能进行分析。结果表明:薄膜具有c轴择优取向。随沉积温度升高,薄膜的结晶度先提高后下降,晶粒尺寸逐渐减小。当沉积温度为200℃时,可获得晶粒尺寸为18.30 nm、电阻率为4.1×10~(-3)Ω·cm、透过率为93.80%的AZO透明导电薄膜。     

Characteristics of atomic layer deposited transparent aluminum-doped zinc oxide thin films at low temperature

Various aluminum-doped zinc oxide(AZO) films were prepared on Si substrate by atomic layer deposition(ALD) at 100℃. The effect of the composition of AZO films on their electrical, optical characteristics,structural property and surface topography was investigated. The appearance of electrical resistivity shows their semiconducting properties. In most of the visible light band, all the AZO films present transparency of more than 80%. Al doping suppresses the AZO film crystallization.When the Al doping concentration increases up to 3.95 at%, the AZO film has some small multicrystal grains with random orientation. Al doping improves the roughness of i-ZnO film. The root mean square(RMS) roughness of samples prepared by ALD is much smaller than that prepared by radio-frequency magnetron sputtering reported.     

Influence of growth temperature on the optical and structural properties of ultrathin ZnO films

This study investigates the effect of growth temperature on the optical and structural properties of ultrathin ZnO films on the polished Si substrate. Thickness of the ultrathin ZnO films deposited by atomic layer deposition (ALD) method was about 10 nm. Photoluminescence (PL), X-ray diffraction (XRD), transmission electron microscopy (TEM) and atomic force microscopy (AFM) techniques were used to measure the properties of ultrathin ZnO films. Experimental results showed that the ultrathin ZnO film deposited at 200 °C had excellent ultraviolet emission intensity, and the average roughness of the film surface was about 0.26 nm.     

Structure and magnetic properties of columnar Fe-N thin films deposited by direct current magnetron sputtering

Columnar Fe-N thin films with thickness ranging from 30 to 150 nm were deposited by direct current magnetron sputtering using an Ar/N2 gas mixture (V(N2)/V(N2+Ar)=5%) on corning glass substrates. The structure, surface morphology and magnetic properties were investigated using X-ray diffractometry(XRD), scanning electron microscopy, atomic force microscopy, transmission electron microscopy(TEM) and superconducting quantum interference magnetometry. XRD investigation shows that Fe-N films exhibit amorphous-like structures; however, TEM measurements indicate the synthesis of mixture phases of α-Fe+ζ-Fe2N+ε-Fe3N in these films. The magnetic anisotropy and coercivity of Fe-N thin films exhibit strong dependence on the film growth behavior and surface morphology. With increasing the height of Fe-N films with column structures, the coercivity increases from 7.96 kA/m to 22.28 kA/m in the direction parallel to the film surface. In perpendicular direction the coercivity only increases slightly from 39.79 kA/m to 43.77 kA/m. However, the values of anisotropy field increase from 0.79×106 to 1.44×106 A/m, which is mainly attributed to the shape anisotropy of elongated columns due to the fact that the difference of magneto-crystalline anisotropy among these Fe-N films is small. The saturation magnetizations of Fe-N films vary with increasing film thickness from 23.5 to 85.1 A-m2/kg.     

具有Al2O3阻挡层的HfO2栅介质膜的界面和电学性能的表征

研究了经过700℃快速热退火的并在Si界面处插入Al2O3阻挡层的HfO2栅介质膜的界面结构和电学性能.X射线光电子谱表明,退火后,界面层中的siOx转化为化学当量的SiO2,而且未发现铪基硅酸盐和铪基酸化物.由电学测试提取出等效栅氧厚度为2.5nm,固定电荷密度为-4.5×1011/cm2.发现Al2O3阻挡层能有效地阻止Si原子扩散进入HfO2薄膜,进而改善HfO2栅介质膜的界面和电学性能.     

ALD沉积HfO_2薄膜生长行为及其调控

采用原子层沉积(ALD)的方法,选择四二乙基氨基铪(TDEAH)和水作为反应前驱体,在p型(100)单晶硅衬底上制备了HfO_2高介电质薄膜。系统研究了前驱体流量、反应气压、反应温度等工艺参数对HfO_2薄膜生长质量的影响。通过工艺调控,发现存在两种薄膜生长模式:类CVD(化学气相沉积)生长模式和ALD生长模式。发现薄膜的生长模式主要依赖于制备工艺参量:脉冲参量M和冲洗参量Q,通过优化工艺参数,可实现薄膜生长由类CVD生长模式向ALD生长模式的转变,并获得了0.1 nm/周次的最优薄膜生长速率。同时,薄膜微结构与表面形貌的表征结果表明:薄膜的非晶晶态转变受温度和膜厚两个因素共同控制。     

表面施加含稀土氧化物薄膜对Fe25Cr高温氧化的"活性元素效应"

研究了表面施加含有不同量Y     

Formation and capacitance properties of Ti-Al composite oxide film on aluminum

Al specimens were covered with TiO2 film by sol-gel dip-coating and then anodized in ammonium adipate solution. The structure, composition and capacitance properties of the anodic oxide film were investigated by transmission electron microscopy (TEM), Auger electron spectroscopy (AES), X-ray diffractometry (XRD) and electrochemical impedance spectroscopy (EIS). It was found that an anodic oxide film with a dual-layer structure formed between TiO2 coating and Al substrate. The film consisted of an inner Al2O3 layer and an outer Ti-Al composite oxide layer. The thickness of layers varied with the number of times of sol-gel dip-coating. The capacitance of anodic oxide films formed on coated specimens was at most 80% higher than that without TiO2. In film formation mechanism, it was claimed that the formation of composite oxide film was mainly affected by the structure of micro-pores network in TiO2 coating which had an influence on Al3+ and O2- ions transport during the anodizing.     

Ta12W合金表面离子束沉积薄膜与U-Nb合金之间的摩擦性能

采用离子束沉积方法在Ta12W合金表面制备了Sn,In软金属薄膜,Al2O3陶瓷薄膜和In/Al2O3复合薄膜.利用销盘摩擦磨损试验机并结合SEM观察分析了对偶销为U-Nb合金时,试样的摩擦学性能并讨论了摩擦磨损机理.当用SiC对偶进行评价时,Sn,In软金属薄膜降低了Ta12W合金摩擦系数.然而当对偶销改为工程状态的U-Nb合金时,由于用离子束溅射沉积法制备的Sn薄膜太薄、In薄膜与U-Nb合金发生粘着,Sn,In软金属薄膜与In/Al2O3复合薄膜均未降低Ta12W合金的的摩擦系数.当Sn薄膜增加到一定厚度时,摩擦性能得到明显改善.Al2O3陶瓷薄膜与U-Nb合金对偶销摩擦时,与Ta12W合金表面直接摩擦结果一样,由于U-Nb合金容易被磨损而使磨屑转移到试样表面,摩擦系数没有下降.     

原子力显微镜和白光干涉仪在表面材料测试中的应用研究

目的验证原子力显微镜和白光干涉仪分别在表面材料测试中的分辨率及其在不同类型表面材料测试中的适用性。方法分别采用原子力显微镜和白光干涉仪,对不同厚度级别的ZnO薄膜、石墨烯、磨斑等几种不同类型的表面材料进行了具体的测试研究。结果白光干涉仪10×镜头和50×镜头及原子力显微镜皆可以准确地测试百纳米级别的ZnO薄膜厚度,测得的膜厚分别为148.668、123.354、111.648 nm。原子力显微镜也可以准确地测出十纳米级别的ZnO薄膜厚度,测得的膜厚仅为6.152 nm,而白光干涉仪则不能测试出十纳米级别的ZnO薄膜厚度。原子力显微镜可以准确地测试出石墨烯片的大小、厚度和层数等三维数据,测得的厚度为0.665 nm左右,层数为单层或双层,而白光干涉仪则没有如此高的分辨率。白光干涉仪可以准确地测试出磨斑的宽度、深度等三维数据,测得的磨斑深度为4.245μm,而原子力显微镜则不适合测试表面如此粗糙的样品。结论原子力显微镜适合于测试相对光滑的表面材料的三维形貌和数据,如测试十纳米级别以上的薄膜厚度、超薄石墨烯片厚度和层数。白光干涉仪则适合于测试相对粗糙的表面材料的三维形貌和数据,如测试百纳米级别以上的薄膜厚度、微米级别磨痕深度等。     

Suppressing the surface roughness and columnar growth of silicon nitride films

The growth and structure evolution of silicon nitride films prepared by radio frequency magnetron sputtering at low pressure were investigated for thickness changes. Grazing-incidence X-ray reflectivity, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy were used to study the structure, surface roughness and composition, respectively, of the films. It was found that with an increase in thickness from 5 to 830 nm, the silicon nitride films have a similar surface structure and their surface roughness only slightly increases. The surface roughness of all the silicon nitride films is only a little more than 0.2 nm, much less than previously reported results. AFM measurement of the fractured film surface indicated that thin silicon nitride films with a thickness below approximately 300 nm have a dense, smooth and uniform structure, and columnar structures gradually appear only in thick films. These results are mainly attributed to the special design of the sputtering system and the energetic particle bombardment of the growing surface, by which the surface roughness and columnar growth were suppressed.