退火温度对磁控溅射制备的β-FeSi2薄膜的影响

采用磁控溅射的方法，在高真空条件下，沉积金属Fe到Si（100）衬底上，然后通过真空退火炉在不同温度条件下对样品进行热处理，直接形成了β-FeSi2薄膜．采用X射线衍射仪（XRD）对样品进行了晶体结构分析，利用卢瑟福背散射（RBS）对Fe-Si化合物的形成过程中的Fe原子和Si原子的互扩散机理进行了研究，利用扫描电镜（SEM）对样品表面的显微结构进行表征，结果表明，在900℃条件下退火能够得到质量很好的β-FeSi2薄膜，超过这一温度β相将开始向α相转化，到1000℃，β-FeSi2全部转化为α-FeSi2。     

立方相MgxZn1-xO纳米晶体薄膜的物理特性

介绍了在Si衬底和石英玻璃衬底上生长的立方相MgxZn1-xO(0.55≤x≤1)晶体薄膜的物理特性,AFM和XRD等微结构特性表征显示了良好的表面形貌和高度的(111)取向生长特性.采用Manifacier方法,根据透射光谱中的干涉峰,计算得到立方相MgxZn1-xO薄膜的折射率.与已报道的六方相MgxZn1-xO(0≤x≤0.5)薄膜的折射率相类似,在400～800nm的可见光区域,不同Mg含量的立方相MgxZn1-xO薄膜,其折射率随入射波长的色散关系遵循一阶Sellmeier方程.对给定400nm的入射光波长,当薄膜中的Mg含量由55%增至100%时,其折射率由1.89衰减至1.73.     

退火对立方相 MgxZn1-xO薄膜的结构和光学性质影响

在蓝宝石（0001）衬底上低温生长立方相MgxZn1-xO（x〉0．5）晶体薄膜，用X射线衍射（XRD）和透射光谱分析高温退火对薄膜的结构和光学性质的影响．结果表明;对Mg0．53Zn0．47O薄膜，在900℃的退火温度下，（0002）衍射峰以及透射光谱上双吸收边的出现均表明有六方结构从其立方结构中分离出来；但对于Mg含量高于55％的样品，即使经历了1000℃的高温退火，也不会有任何相分裂现象出现．而电学测试结果表明，高温下热稳定性良好的立方相Mg0．55Zn0．45O晶体薄膜还能用于金属-绝缘体-半导体的绝缘层，并且漏电流小．由此可以判断，x≥0．55的超饱和MgZn1-xO薄膜具有稳定的立方相晶体结构和优良的光学、电学性质，因而是制作高质量的光电子器件和量子阱激光器的理想材料．     

MgxZn1-xO薄膜的红外光谱及其表面浸润性

采用溶胶-凝胶法制备MgxZn1-xO薄膜,利用X射线衍射仪、原子力显微镜、傅里叶变换红外光谱仪和荧光光谱仪等测试分析薄膜的微结构、表面形貌、红外光谱和光致发光特性等,研究结果表明,薄膜中的Zn O成分均呈六角纤锌矿结构,当x=0.15时,薄膜中有Mg O成分析出;随着x从0增大到0.15,均方根粗糙度不断减小;1038 cm-1附近的吸收峰对应于Si-O-Si的对称和反对称伸缩振动模,408 cm-1附近的吸收峰对应于六角结构Zn O的Zn-O振动模,900 cm-1附近的吸收峰则对应于SiO键伸缩振动模,该吸收峰强度的减弱说明薄膜中Si-O键数目减少。近带边发射峰位由410 nm蓝移到370 nm与薄膜导带底或价带顶的局域能级、薄膜禁带宽度变化等因素有关,可见光发射带是单离子氧空位(VO+)和氧填隙(Oi)等薄膜本征缺陷相互竞争的结果。用接触角测试仪测试薄膜的表面接触角,研究Mg含量对薄膜的表面浸润性及其光诱导可逆转变的影响,并探讨其形成机理。     

H2气氛退火处理温度对磁控溅射ZnO薄膜光电性能的影响

在室温下,采用直流磁控溅射法,以载玻片作为衬底,淀积出ZnO薄膜。在常压H2气氛中,以不同温度对样品进行退火处理。结果表明,在退火温度为500℃时,样品具有最佳综合光电性能,其在360～960nm波长范围内的平均透光率为76.35%,方块电阻为6.3kΩ/□。     

WO3薄膜退火热处理工艺的研究

采用真空镀膜工艺在微晶玻璃衬底上沉积了WO3薄膜,WO3薄膜从300～600℃分别进行了退火热处理,随着退火热处理温度的不同,WO3薄膜从晶粒尺寸上以及晶相上都发生了较大的变化,并用SEM、XRD等手段进行了分析,随着退火热处理温度的升高,WO3晶粒逐渐增大,并实现了从非晶向晶态的转变,最终得到了六方结构并且是在[100]方向上择优取向的WO3薄膜,获得了稳定性较好的工艺条件,为进一步开发研制WO3气敏元件提供了技术基础.     

退火对低温射频磁控溅射Ba铁氧体薄膜结构及磁特性的影响

用ＲＦ磁控溅射法，在纯Ａｒ气中，硅基片不加热的情况下，制备了Ｂａ铁氧化薄膜，研究了退火温度对薄膜Ｃ轴垂直取向、结构及磁特性的影响，结果表明薄膜在７００℃氧气中退火可获得良好Ｃ轴垂直膜同的择优取向，该薄膜的饱和磁化强度和矫顽力分别为Ｍｓ＝２９６ｅｍｕ／ｃｍ＾３，Ｈｃ＝３０８７６１Ａ／ｍ。退火温度过低或过高，都不利于形成Ｃ轴垂直膜面的择优取向。     

退火对低温射频磁控溅射Ba铁氧体薄膜结构及磁特性的影响

用RF磁控溅射法，在纯Ar气中，硅基片不加热的情况下，制备了Ba铁氧体薄膜，研究了退火温度对薄膜c轴垂直取向、结构及磁特性的影响，结果表明薄膜在700℃氧气中退火可获得良好c轴垂直膜面的择优取向，该薄膜的饱和磁化强度和矫顽力分别为Ms=296emu／cm3，Hc=308761A／m。退火温度过低或过高，都不利于形成c轴垂直膜面的择优取向。     

退火温度对磁控溅射SiC薄膜结构和光学性能的影响

首先采用射频磁控溅射法在单晶Si(100)衬底上沉积制备了SiC薄膜,然后将所制备的薄膜试样分别在600,800和1 000℃氩气氛中退火120 min;采用X射线衍射仪和红外吸收光谱仪分析了薄膜的结构随退火温度的变化,采用荧光分光分度计研究了薄膜的发光性能随退火温度的变化。结果表明:室温制备的SiC薄膜为非晶态,经600℃退火后薄膜结晶,且随着退火温度的升高,薄膜的结晶程度越来越好,并且部分SiC结构发生了由α-SiC到β-SiC的转变;所制备的SiC薄膜在384和408 nm处有两个发光峰,且两峰的强度均随退火温度的升高逐渐变强,其中384nm处的峰源自于SiC的发光,408 nm处的峰源自于碳簇的发光。     

退火对sol-gel法生长的SiO2薄膜特性的影响

用正硅酸乙酯(ETOS),乙醇(EtOH),水以及盐酸以一定的比例混合配制溶胶(其中盐酸为催化剂).以普通浮法玻璃为衬底,用浸渍提拉法制备了厚度为100nm左右的SiO2薄膜.对其进行等温和等时退火,用台阶仪测定其厚度变化,给出经验拟合公式.研究了退火对透过率、折射率以及气孔率的影响,并做出比较详细的理论解释.     

Properties of TaSiN thin films deposited by reactive radio frequency magnetron sputtering

TaSiN is a promising material for application as electrically conductive diffusion barrier for the integration of high permittivity perovskite materials in integrated circuits. TaSiN thin films were deposited by reactive radio frequency magnetron sputtering using TaSi and TaSi_2.7 targets in an Ar/N₂ atmosphere. The sputter power was varied in order to achieve different TaSiN compositions. The stoichiometry of as-deposited films was estimated using Rutherford backscattering spectroscopy. The as-deposited TaSiN thin films are amorphous. Their crystallization temperature is above 700 °C and increases with higher nitrogen content. They have metallic conduction and ohmic behavior. The resistivity of as deposited films is in the range from 10^− 6 Ω m up to 10^− 3 Ω m and increases with nitrogen content. It was found that p⁺⁺-Si/Ta₂₁Si₅₇N₂₁ develops unacceptable high contact resistance. Introducing an intermediate Pt layer the stack p⁺⁺-Si/Pt/Ta₂₁Si₅₇N₂₁ had a good conductive properties and good thermal stability at 700 °C.     

Cu2O thin films deposited by reactive direct current magnetron sputtering

The Cu₂O thin films were prepared on quartz substrate by reactive direct current magnetron sputtering. The influences of oxygen partial pressure and gas flow rate on the structures and properties of deposited films were investigated. Varying oxygen partial pressure leads to the synthesis of Cu₂O, Cu₄O₃ and CuO with different microstructures. At a constant oxygen partial pressure of 6.6 × 10^− 2 Pa, the single Cu₂O films can be obtained when the gas flow rate is below 80 sccm. The as-deposited Cu₂O thin films have a very high absorption in the visible region resulting in the visible-light induced photocatalytic activity.     

溅射法生长 MgxZn1- xO薄膜的结构和光学特性

用射频磁控溅射法在不同衬底上制备出了MgxZn1-xO薄膜。X射线衍射(XRD)和原子力显微镜(AFM)研究结果表明,薄膜为六角纤锌矿结构,具有(002)方向择优取向;随氧分压增加,(002)衍射峰的角度变大,表征薄膜表面粗糙程度的方均根粗糙度减小。室温光致发光谱中有多个紫外及可见光致发光峰,其中344nm发光峰应来源于近带边发射。室温透射谱表明薄膜在可见光区具有极高的透过率,薄膜的吸收边位于340nm附近,进而估算出Mg、Zn1-xO薄膜的带隙宽度为3．59eV,与光致发光结果一致。     

Indium tin oxide films deposited on polyethylene naphthalate substrates by radio frequency magnetron sputtering

Indium tin oxide (ITO) thin films were deposited on unheated polyethylene naphthalate substrates by radio-frequency (rf) magnetron sputtering from an In₂O₃ (90 wt.%) containing SnO₂ (10 wt.%) target. We report the structural, electrical and optical properties of the ITO films as a function of rf power and deposition time. Low rf power values, in the range of 100-130 W, were employed in the deposition process to avoid damage to the plastic substrates by heating caused by the plasma. The films were analyzed by X-ray diffraction and optical transmission measurements. A Hall measurement system was used to measure the carrier concentration and electrical resistivity of the films by the Van der Pauw method. The X-ray diffraction measurements analysis showed that the ITO films are polycrystalline with the bixbite cubic crystalline phase. It is observed a change in the preferential crystalline orientation of the films from the (222) to the (400) crystalline orientation with increasing rf power or deposition time in the sputtering process. The optical transmission of the films was around 80% with electrical resistivity and sheet resistance down to 4.9 × 10^- 4 Ωcm and 14 Ω/sq, respectively.     

Phase transitions of room temperature RF-sputtered ZnO/Mg0.4Zn0.6O multilayer thin films after thermal annealing

We report the thermal stability of room-temperature RF-sputtered Mg_0.4Zn_0.6O thin films and ZnO/Mg_0.4Zn_0.6O superlattices at 600 °C and 800 °C. The phase of room-temperature as-sputtered Mg_0.4Zn_0.6O is crystalline ZnO embedded in an amorphous or short-range-ordered hexagonal MgZnO matrix. Annealing at either 600 °C or 800 °C for 5 min transforms the matrix into a crystalline hexagonal wurtzite structure, leading to a decrease of the optical bandgap (E_g) of Mg_0.4Zn_0.6O. This also results in a slight change near the absorption edge of the superlattice transmission spectrum. The films precipitate cubic MgZnO after heating Mg_0.4Zn_0.6O at 800 °C for 5 min; by contrast, precipitations take at least 3 h if the samples are heated at 600 °C. Heating at 800 °C for more than 3 h significantly reduces the film thickness and E_g, attributed to the decomposition of superlattices and diffusion of magnesium into the substrate, respectively. On the other hand, annealing the ZnO/Mg_0.4Zn_0.6O superlattice at 600 °C for 12 h also produces an initial slight change in the optical transmission spectra, yet the spectra remain essentially unchanged for the remainder of the annealing process.     

Thin-film transistors with sol-gel deposited Mg0.1Zn0.9O films as active channel layer

We report on field-effect transistors using Mg_0.1Zn_0.9O thin film as channel layer. The effect of Mg is to increase the band gap and decrease the electron carrier concentration. The Mg_0.1Zn_0.9O film deposited by sol-gel method has a highly c-axis orientation and excellent optical properties. The devices display a channel mobility of 0.76 cm² V^− 1 s^− 1 and an on/off ratio of 400.     

Influence of annealing on thermoelectric properties of bismuth telluride films grown via radio frequency magnetron sputtering

Bismuth telluride films were prepared via radio frequency magnetron sputtering. Mixed powders with different composition were used as sputtering targets. Influence of the annealing temperature on surface topography, crystal structure and thermoelectric properties of the films has been investigated. It was found that the grain size increased and the surface roughness decreased with a rising annealing temperature. X-ray diffraction analysis revealed an improved crystallization after the annealing, and that crystal planes perpendicular to c-axis became prominent. High temperature treatments resulted in a decrease of Seebeck coefficient and an increase of electrical conductivity. The highest power factor was obtained after being annealed at 300 °C.     

Structural and optoelectronic properties of Al-doped zinc oxide films deposited on flexible substrates by radio frequency magnetron sputtering

Al-doped zinc oxide (AZO) thin films were deposited onto flexible polyethylene terephthalate substrates, using the radio frequency (RF) magnetron sputtering process, with an AZO ceramic target (The Al₂O₃ content was about 2 wt.%). The effects of the argon sputtering pressure (in the range from 0.66 to 2.0 Pa), thickness of the Al buffer layer (thickness of 2, 5, and 10 nm) and annealing in a vacuum (6.6 × 10^− 4 Pa), for 30 min at 120 °C, on the morphology and optoelectronic performances of AZO films were investigated. The resistivity was 9.22 × 10^− 3 Ω cm, carrier concentration was 4.64 × 10²¹ cm^− 3, Hall mobility was 2.68 cm²/V s and visible range transmittance was about 80%, at an argon sputtering pressure of 2.0 Pa and an RF power of 100 W. Using an Al buffer decreases the resistivity and optical transmittance of the AZO films. The crystalline and microstructure characteristics of the AZO films are improved by annealing.     

Effects of hydrogen gas on properties of tin-doped indium oxide films deposited by radio frequency magnetron sputtering method

Tin-doped indium oxide (ITO) films were deposited at ∼ 70 °C of substrate temperature by radio frequency magnetron sputtering method using an In₂O₃-10% SnO₂ target. The effect of hydrogen gas ratio [H₂ / (H₂ + Ar)] on the electrical, optical and mechanical properties was investigated. With increasing the amount of hydrogen gas, the resistivity of the samples showed the lowest value of 3.5 × 10^− 4 Ω·cm at the range of 0.8-1.7% of hydrogen gas ratio, while the resistivity increases over than 2.5% of hydrogen gas ratio. Hall effect measurements explained that carrier concentration and its mobility are strongly related with the resistivity of ITO films. The supplement of hydrogen gas also reduced the residual stress of ITO films up to the stress level of 110 MPa. The surface roughness and the crystallinity of the samples were investigated by using atomic force microscopy and x-ray diffraction, respectively.     

Influence of annealing temperature on the properties of ZnO:Zr films deposited by direct current magnetron sputtering

Transparent conducting zirconium-doped zinc oxide (ZnO:Zr) films were deposited on quartz substrates by direct current (DC) magnetron sputtering at room temperature. The influence of post-annealing temperature on the structural, morphological, electrical and optical properties of ZnO:Zr films were investigated. When annealing temperature increases from room temperature to 573 K, the resistivity decreases obviously due to an improvement of the crystallinity. However, with further increase in annealing temperature, the crystallinity deteriorates leading to an increase in resistivity. The films annealed at the optimum annealing temperature of 573 K in vacuum have the lowest resistivity of 9.8 × 10⁻⁴ Ω cm and a high transmittance of above 92% in the visible range.