氧气流量对射频磁控溅射制备Cu2O薄膜性能的影响

通过磁控溅射方法在玻璃衬底上制备Cu2O薄膜,采用X射线衍射(XRD)、分光光度计、原子力显微镜(AFM)和X射线光电子能谱(XPS)等研究了氧气流量对Cu2O薄膜性能的影响.结果表明:氧气流量为4.2 sccm时,薄膜为单相的Cu2O,具有较高的结晶质量和可见光透过率,光学带隙为2.29 eV,薄膜的导电类型是p型且空穴浓度为2×1016 cm-3.通过XPS能谱分析Cu 2p3/2和O 1s结合能,确定了薄膜中Cu以+1价存在.     

结晶β-C3N4薄膜的制备和特性研究

用电子回旋共振等离子体化学汽相沉积(ECR CVD)法, 在单晶硅(100)衬底上沉积生长出了具有{221}结构特性的连续的结晶态β-C3N4薄膜.使用扫描电镜(SEM)观测了沉积薄膜的形态;采用X射线光电子光谱(XPS),X射线衍射(XRD)和拉曼散射表征薄膜的结构.研究表明,沉积结晶态β- C3N4薄膜具有{221}结构特性.     

硼碳氮纳米管的溶剂热法制备及其表征

以无水CH3CN*BCl3和Li3N为原料,以苯为溶剂,在温度为330℃,压力为8～9MPa条件下,利用溶剂热合成方法成功地制备出了BCN三元化合物.X射线粉末衍射(XRD)分析表明,产物为类石墨态结构,透射电子显微镜(TEM)观测到产物中含有B-C-N纳米管.X射线能谱(XPS)和Fourier变换红外光谱(FTIR)分析表明硼碳氮是以原子级化合的形式存在.     

热丝辅助射频CVD C3N4薄膜

采用热丝辅助射频等离子体增强化学气相沉积(CVD)方法直接在Si(100)衬底上制备了多晶C3N4薄膜.X射线衍射(XRD)测试表明薄膜同时含有α-C3N4和β-C3N4晶相以及未知结构.傅立叶变换红外吸收谱(FTIR)表明薄膜内的C-N, C＝N和 C≡N 键的吸收峰分别位于1237,1625和2191cm-1.利用扫描电子显微镜(SEM)观测到线度约为2μm、横截面为六边形的β-C3N4晶粒.纳米压痕法测得薄膜的硬度最高可达72.66GPa.     

真空蒸发法制备ZnSe薄膜的X射线光电子能谱研究

本文用真空蒸发法制备了CIS太阳能电池中做缓冲材料的ZnSe薄膜,利用X射线光电子能谱(XPS)对制备薄膜的表面化学状态及沉积质量进行了研究,并用氩离子溅射进行剥蚀,逐层分析薄膜的化合态随深度的变化关系.XPS分析表明,ZnSe薄膜含有Zn、Se、O、C等元素,其中O、C为样品置于空气中所致,含量随剥蚀深度的加大而逐渐降低.Zn的光电子峰为Zn2p1/2和Zn2p3/2,Zn2p3/2的电子结合能为1021.90eV,对应着Zn2+的化合态,表明薄膜中zn以形式电荷为Zn2+的化合态形式存在;Se的光电子峰为Se3d,其电子结合能为54.30eV,对应着Se2-的化合态,表明薄膜中Se以形式电荷Se2-的化合态形式存在.分别经过1min、3min、7min、11min的剥蚀后,Zn和Se的光电子峰几乎没有改变,表明沉积的ZnSe薄膜表面和内部化学状态稳定一致.     

用MPCVD法制备氮化碳薄膜

用微波等离子体化学气相沉积法(MPCVD)在硅片和铂基片上生长了氮化碳薄膜.扫描电镜(SEM)观察显示,在硅片上形成了多晶的膜;EDX能谱分析表明膜中的碳氮比在1.0～2.0之间;X射线衍射谱表明在硅片和铂片上生长的氮化碳薄膜是由α-C3N4和β-C3N4晶相组成的;XPS峰形分析表明,薄膜中的C、N主要是以共价单键结合的;红外谱中也出现了β-C3N4的特征谱线.因此有足够的证据表明,晶态的氮化碳薄膜已经合成.     

掺氮四配位非晶碳薄膜的拉曼光谱和表面形貌

采用磁过滤真空溅射离子沉积技术,用氩气和氮气共溅射石墨靶,在不同氮气分压下,制备了一组不同氮含量的四配位非晶碳薄膜(ta-C:N).用X射线光电子能谱确定ta-C:N薄膜中的氮含量;研究了氮含量对ta-C薄膜的拉曼光谱和表面形貌的影响.结果表明:不含氮的ta-C薄膜的拉曼光谱是中心在1580cm-1、范围从1200cm-1至2000cm-1的类高斯峰,表面均匀光滑;含氮的ta-C:N薄膜,其拉曼光谱分裂为1360 cm-1的D带和1580 cm-1的G带,且D带与G带的最大强度比, 以及薄膜的表面粗糙度随氮含量的增加而增大.最后讨论了氮含量对ta-C薄膜的微结构的影响.     

射频磁控溅射法制备TiO2-xNx薄膜的结构性能研究

利用射频磁控溅射法室温下在Si(100)衬底上制备了N掺杂的TiO2薄膜,并且采用x射线衍射(XRD)、X射线光电子能谱(XPS)和透射光谱对薄膜进行了表征.XRD结果表明在纯Ar和N2(33.3;)/Ar气氛下制备的TiO2-xNx薄膜均为单一的金红石相,薄膜结晶性良好,呈高度(211)择优取向,而在N2(50.0;)/Ar下制备的薄膜结晶性明显变差;对于N掺杂的TiO2薄膜,XPS表明部分N原子进入TiO2晶格,并且以N-Ti-O、N-O键以及间隙式N原子形式存在;透射光谱表明掺N后的TiO2薄膜吸收边发生了红移.     

微波等离子体化学气相沉积制备碳氮晶体薄膜

利用微波等离子体化学气相沉积系统 ,以甲烷、氮气和氢气作为气源 ,在Si( 1 0 0 )衬底上成功地制备出了碳氮晶体薄膜 ,并对两种衬底温度下的薄膜性质进行了比较。用高分辨率场发射扫描电子显微镜观察薄膜 ,可以看出晶型完整 ,结构致密 ,结晶质量较好。X射线能谱证明了碳氮是以C─N和CN共价键的形式存在 ,氮碳元素的原子比均为 1 .3。X射线衍射确定出在衬底温度为 90 0± 1 0℃时薄膜样品的主要晶相成份是α C3N4,β C3N4,赝立方C3N4,立方C3N4和一个未知相 (面间距d =0 .4 0 0 2nm) ,而在 95 0± 1 0℃时薄膜样品的主要晶相成份是α C3N4,β C3N4,赝立方C3N4,类石墨C3N4和一个未知相 (面间距d =0 .3 984nm)。喇曼光谱分析也证实了薄膜中主要存在α C3N4,β C3N4相     

CdSe纳米晶薄膜的制备与特性研究

采用真空热蒸发技术,在光学玻璃基片上生长出排列整齐、高质量的CdSe纳米晶薄膜.通过X射线衍射(XRD)、X射线光电子能谱分析(XPS)、扫描电镜(SEM)、傅里叶红外光谱(IR)等进行表征.结果表明,薄膜结晶性能较好,纳米晶颗粒约为40 ～70 nm,呈半月状,排列整齐;化学元素配比为49.4∶50.6,稍微富Se;红外透过率高,禁带宽度为1.89 eV,高于块状的CdSe晶体(1.70 eV).     

AlN/Si(100)上CVD SiC薄膜的光致发光谱

本工作用化学气相淀积方法在AlN/Si(100)复合衬底上生长SiC薄膜.外延生长过程中,采用C4H4和SiH4作为反应气源,H2作为载气.样品的X-射线衍射谱和拉曼散射谱显示,所得到的外延层为六角对称的SiC薄膜.俄歇电子能谱及X-射线光电子能谱的测量结果表明,在外延膜中存在来自衬底的Al和N元素.样品的光致发光测量显示,所有的样品均可在室温下观察到位于3.03eV和3.17eV处的发光峰,这分别相应于4H-SiC能带中电子从导带到Al受主能级之间的辐射跃迁和电子从N施主能级到价带之间的辐射跃迁,从而表明所得的外延薄膜的多形体为4H-SiC.     

Effect of N2/CH4 flow ratio on microstructure and composition of hydrogenated carbon nitride films prepared by a dual DC-RF plasma system

Hydrogenated carbon nitride (a-CN:H) films were deposited on n-type (1 0 0) silicon substrates making use of direct current radio frequency plasma enhanced chemical vapor deposition (DC-RF-PECVD), using a gas mixture of CH₄ and N₂ as the source gas in range of N₂/CH₄ flow ratio from 1/3 to 3/1 (sccm). The deposition rate, composition and bonding structure of the a-CN:H films were characterized by means of X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectrometry (FTIR). The mechanical properties of the deposited films were evaluated using nano-indentation test. It was found that the parameter for the DC-RF-PECVD process had significant effects on the growth rate, structure and properties of the deposited films. The deposition rate of the films decreased clearly, while the N/C ratio in the films increased with increasing N₂/CH₄ flow ratio. CN radicals were remarkably formed in the deposited films at different N₂/CH₄ flow ratio, and their contents are related to the nitrogen concentrations in the deposited films. Moreover, the hardness and Young’s modulus of the a-CN:H films sharply increased at first with increasing N₂/CH₄ flow ratio, then dramatically decreased with further increase of the N₂/CH₄ flow ratio, and the a-CN:H film deposited at 1/1 had the maximum hardness and Young’s modulus. In addition, the structural transformation from sp³-like to sp²-like carbon-nitrogen network in the deposited films also was revealed.     

Influence of the nitrogen flow rate on the order and structure of PECVD boron nitride thin films

Three sets of boron nitride (BN) thin films are deposited with different N₂/B₂H₆ flow ratios (r = 4, 10 and 25) by plasma enhanced chemical vapor deposition (PECVD). The variations of physical properties in different deposition sets are analyzed by optical (XPS, FTIR, UV–visible spectroscopies), mechanical and electrical measurements. The films are considered to be deposited in a turbostratic phase (t-BN). Evolution of bonding configurations with increasing r is discussed. Relatively higher nitrogen flow rate in the source gas mixture results in lower deposition rates, whereas more ordered films, which tend to reach a unique virtual crystal of band gap 5.93 eV, are formed. Anisotropy in the film structure and film inhomogeneity along the PECVD electrode radial direction are investigated.     

Effect of deposition pressure on microstructure and properties of hydrogenated carbon nitride films prepared by DC-RF-PECVD

Hydrogenated carbon nitride (a-CN:H films) were deposited on n-type (1 0 0) silicon substrates making use of dual direct current radio frequency plasma enhanced chemical vapor deposition (DC-RF-PECVD), at working pressure of 2–20 Pa, using a mixed gas of CH₄ and N₂ as the source gas. The growth rate, composition, bonding structure of the deposited films were characterized by means of XPS and FTIR, and the mechanical properties of the deposited films were investigated by nano-indentation test. It was found that the parameters for the DC-RF-PECVD process had significant effects on the growth rate, structure and properties of the deposited films. The growth rate of the deposited films increased at first with increasing deposition pressure, then saturated with further increase of the deposition pressure. The N/C ratio inside the deposited films increased with increasing working pressure except that it was as much as 0.50 at a working pressure of 5.0 Pa. The nano-hardness of the films decreased with increasing deposition pressure. CN radicals were remarkably formed in the deposited films at higher pressures, and their contents are related to the nitrogen concentrations in the deposited films.     

1H-1,2,3-triazole,a promising precursor for chemical vapor deposition of hydrogenated carbon nitride

Well-crystallized hydrogenated carbon nitride thin films have been prepared by microwave plasma enhanced chemical vapor deposition (MWPECVD). 1H-1,2,3-triazole+N₂ and Si (1 0 0) were used as precursor and substrate, respectively. Substrate temperature during the deposition was recorded to be 850 °C. The synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photo-electron spectroscopy (XPS) analyses. The plasma compositions were checked by optical emission spectroscopy (OES). XRD observation strongly suggests that the films contain polycrystalline carbon nitride with graphitic structure of (1 0 0), (0 0 2), (2 0 0) and (0 0 4). XPS peak quantification reveals that the atomic ratio of the materials C:N:O:Si is 32:41:18:9. X-ray photo-electron peak deconvolution shows that the most dominant peak of C (1s) and N (1s) narrow scans correspond to sp² hybrid structure of C₃N₄. These observations indicate that 1H-1,2,3-triazole favors the formation of hydrogenated carbon nitride with graphitic phase by CVD method and thus is in good agreement with XRD results. SEM of surface and OES of plasma also support the formation of polycrystalline carbon nitride films from 1H-1,2,3-triazole+N₂ by CVD.     

Structural investigation and electronic band transitions of nanostructured TiO2 thin films

Titanium dioxide (TiO₂) thin film was deposited on n‐Si (100) substrate by reactive DC magnetron sputtering system at 250 °C temperature. The deposited film was thermally treated for 3 h in the range of 400‐1000 °C by conventional thermal annealing (CTA) in air atmosphere. The effects of the annealing temperature on the structural and morphological properties of the films were investigated by X‐ray diffraction (XRD) and atomic force microscopy (AFM), respectively. XRD measurements show that the rutile phase is the dominant crystalline phase for the film annealed at 800 °C. According to AFM results, the increased grain sizes indicate that the annealing improves the crystalline quality of the TiO₂ film. In addition, the formation of the interfacial SiO₂ layer between TiO₂ film and Si substrate was evaluated by the transmittance spectra obtained with FTIR spectrometer. The electronic band transitions of as‐deposited and annealed films were also studied by using photoluminescence (PL) spectroscopy at room temperature. The results show that the dislocation density and microstrain in the film were decreased by increasing annealing temperature for both anatase and rutile phases. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

溶剂热合成氮化硼纳米晶过程中氮源种类的影响

以NaNH2和BC l3为原料,利用溶剂热方法合成了六方氮化硼纳米微晶,并用红外吸收光谱(FTIR)、X射线粉末衍射(XRD)方法分析了微粒的结构,利用透射电子显微镜(TEM)观测了BN微粒的粒度和微观形貌。与早期用L i3N为氮源合成的氮化硼(产物中具有较多纳米棒)相比,本文中制备的氮化硼纳米晶主要呈球形,颗粒粒度明显增大,而且产率有较大幅度的提高。