沉积电流对ZnO薄膜的结构和光学性质的影响

采用阴极电沉积的方法在导电玻璃上制备了ZnO薄膜.研究了沉积电流对薄膜结构特性和光学特性的影响.XRD分析表明ZnO薄膜为纤锌矿结构,晶粒尺寸随电流的增大而增大,择优取向随电流的变化发生了转变.光学测试表明样品的透射率最大值可达84%,禁带宽度随电流变化不大,接近于3.3 eV.     

电镀法制备CoNiMnP永磁薄膜研究

采用电子能谱仪(EDS)与振动样品磁强计(VSM),研究了电流密度及镀液pH值对电镀CoNiMnP永磁薄膜矫顽力的影响。结果表明:CoNiMnP永磁薄膜具有明显的垂直各向异性,且随电流密度和镀液pH值的增大,CoNiMnP薄膜的矫顽力呈先增大后降低的变化;当电流密度为5×10–3A/cm2、镀液pH值为5时,CoNiMnP薄膜垂直方向的矫顽力Hcj达到最大值80kA·m–1。     

高质量CVD金刚石自支撑膜的连续激光损伤研究

利用HJ - 4型连续CO2 激光对金刚石膜进行了激光损伤阈值的研究,损伤后的金刚石膜用SEM和Raman进行了表征。研究结果表明,高质量CVD自支撑金刚石膜具有较高的 激光损伤阈值,金刚石膜抗连续激光损伤阈值的范围是在1. 15 ×106 ～2. 26 ×106W / cm2。金刚石膜激光损伤主要是由于热震损伤,其机制属于热- 力耦合机制。     

等离子增强化学气相沉积法制备Si-C-H薄膜

以SiH4和CH4为气源,在不同的工艺条件下用增强化学气相沉积(PECVD)方法制备了一系列Si-C-H薄膜,并对薄膜的结构和性能进行了一系列测试分析,研究了薄膜的结构性能特点以及CH4/SiH4比和射频功率等工艺参数对薄膜结构和性能的影响。发现薄膜中主要形成的是嵌有Si晶粒的非晶态SiC结构,H原子主要以C-H键形式存在。高的射频功率和CH4/SiH4比均有利于Si-C的形成,而较低的CH4/SiH4比可以提高薄膜的晶态率。薄膜的电阻率随着CH4/SiH4比的增大而增大,随着射频功率的增大而减小。     

Good conductivity of a single component polydiacetylene film

Two films were prepared from single component monomer solutions. In these monomers, diacetylene and two acid groups are licked by flexible side chains. The side chain serves as the spacer between diacetylenes. After UV-irradiation, monomer films were transformed to polydiacetylene films and one of films exhibited conductivity drastically increases. This conductivity is two orders of magnitude greater than the conductivity value of reported nondoped polydiacetylene films.     

化学溶液分解法制备LaNiO3薄膜的研究

采用化学溶液分解法直接在单晶Si(100)衬底上制备了LaNiO3薄膜，研究了不同热处理气氛(空气和氧气)对薄膜的结晶性、晶粒尺寸、电阻率以及其上面生长的锆钛酸铅(PZT)薄膜的影响．结果发现二种气氛得到的LaNiO3薄膜的电阻率相差较大，其中在氧气中制备的薄膜电阻率仅为在空气中得到的1／2．对LaNiO3薄膜的导电机制进行了讨论．     

Ge2Sb2Te5的电化学特性及化学机械抛光

从电化学角度研究了Ge2Sb2Te5薄膜在化学机械抛光液中的作用，以及不同的pH值和H2O2浓度下的电化学特性. 采用Solartron SI1287电化学设备测试了Ge2Sb2Te5薄膜在溶液中的开路电位和动电位扫描. 开路电位结果表明：Ge2Sb2Te5在pH值为10的抛光液中表现出钝化行为；而抛光液的pH值为11时，开始向活化转变；当pH值为12时，薄膜处于活化状态. 在动电位扫描过程中，不同的pH值和H2O2浓度下，薄膜的扫描曲线形状相似，表明薄膜腐蚀具有相同的反应机理. 自制碱性抛光液，对Ge2Sb2Te5薄膜进行化学机械抛光，用SEM和EDS对抛光后的结构进行分析. 结果表明，通过CMP实现了Ge2Sb2Te5填充结构.     

磁光石榴石薄膜的光吸收系数

分析了引起磁光石榴石薄膜光衰减的各种因素,导出了光吸收系数α和光散射系数γ的表达式。采用磁光调制比较法测量了(BiTm)_3(FeGa)_5O_(12)薄膜的α、γ值。与通常方法相比,这种方法不仅消除了衬底吸收,薄膜-衬底界面反射对测量α值的影响,而且可以将γ与α分离开来,从而使得到的α值比较接近于真值。     

透明导电薄膜最佳掺杂含量的理论计算

分析了几种氧化物半导体透明导电薄膜材料的掺杂改性的实验结果,建立了薄膜材料的某一物理性能与晶体结构、制备方法和掺杂剂含量之间的联系,并给出了一个能够拟合实验曲线的抛物线方程.该方程的极值点确定了最佳掺杂含量与晶体结构和制备方法之间的定量关系,进而导出了一个最佳掺杂含量表达式.应用此表达式定量计算了铝掺杂氧化锌薄膜、锡掺杂氧化铟薄膜、锑掺杂二氧化锡薄膜等氧化物半导体透明导电薄膜材料最佳掺杂剂在不同制备方法下的最佳掺杂量.结果表明定量计算的结果与部分实验数据相符合.     

LSCO薄膜的制备及光学性能研究

采用化学溶液沉积法在Pt/TiO2/SiO2/Si衬底上制备LaxSr1-xCoO3(简称LSCO)导电薄膜,对不同的La/Sr比以及掺入Ni的情况下LSCO导电薄膜的红外光学性质进行了比较研究.结果表明:LSCO薄膜的红外吸收与La/Sr的化学计量比值有关,当La/Sr为1∶1时,LSCO薄膜的红外吸收最强;在LSCO薄膜中掺入一定量的Ni后,其红外光吸收将会增强,这说明掺Ni有利于提高基于LSCO薄膜电极的铁电探测器的红外吸收能力.     

Structural and electrical investigation of BLT films deposited at different times using electron beam evaporation technique

Thin films Bi4Ti3O12 (BLT) were deposited using electron beam evaporation on silicon substrate at several times, also on AlN/Si and SiO2/Si substrates. Thin films morphology and thickness were measured via scanning electron microscopy (SEM). The crystallography was studied using X-ray diffraction (XRD) technique for films which have a (0010) preferred orientation in all substrate types. The capacitance values were contingent on frequency value in C-V measurement. The ferroelectric characterization was investigated for BLT film deposited on isolator layer (SiO2 or AlN) for Al/Bi4Ti3O12/SiO2/Si devices. Memory effect value varied from 1 V to 3 V depending on the thin films isolator on substrate.     

Study on the correlation between crystallite size–optical gap energy and precursor molarities of ZnO Thin FilmsS. Benramachea,*, O. Belahssena, A. Guettafb and A. Arif b

We investigated the structural and optical properties of ZnO thin films as an n-type semiconductor. The films were deposited at different precursor molarities using an ultrasonic spray method. In this paper we focused our attention on a new approach describing a correlation between the crystallite size and optical gap energy with the precursor molarity of ZnO thin films. The results show that the X-ray diffraction （XRD） spectra revealed a preferred orientation of the crystallites along the c-axis. The maximum value of the crystallite size of the films is 63.99 nm obtained at 0.1 M. The films deposited with 0.1 M show lower absorption within the visible wavelength region. The optical gap energy increased from 3.08 to 3.37 eV with increasing precursor molarity of 0.05 to 0.1 M. The correlation between the structural and optical properties with the precursor molarity suggests that the crystallite size of the films is predominantly influenced by the band gap energy and the precursor molarity. The measurement of the crystallite size by the model proposed is equal to the experimental data. The minimum error value was estimated by Eq. （4） in the higher crystallinity.     

制备条件对TiO2薄膜结构和光学性能的影响

借调节sol-gel法中溶胶的pH值,薄膜的热处理温度,研究了它们对TiO2薄膜的晶相组成、晶粒大小、表面结构和紫外及可见光吸收性能的影响。结果表明:pH为7时有利于TiO2由锐钛矿向金红石相转变,薄膜的孔隙度为94nm,有较高的表面粗糙度。pH值升高,TiO2薄膜的孔隙度和颗粒度增大;热处理温度升高,薄膜的紫外吸收发生红移,可见光波段透射率降低,故最佳热处理温度为500℃。     

ArF准分子激光立方氮化硼薄膜的制备

采用ＡｒＦ准分子脉冲激光沉积方法（ＰＬＤ），以六方氮化硼（ｈ－ＢＮ）作靶在Ｓｉ（１００）衬底上制备氮化硼薄膜。ＸＲＤ及ＦＴＩＲ透射谱测量表明生成的氮化硼薄膜是含有少量六方氮化硼结构的立方氮化硼（Ｃ－ＢＮ）．ＡＥＳ测量表明不同条件下生成的薄膜中Ｎ与Ｂ的相对含量是不同的，最大比例近乎为１：１，薄膜的维氏显微硬度ＨＶ最大值为１５８０ｋｇ／ｍｍ２。     

Influence of pH on structural,optical and electrical properties of solution processed Cu2ZnSnS4 thin film absorbers

Cu₂ZnSnS₄ (CZTS) films were obtained by the dip-coating method. The effect of different pH values 4.0, 4.5, and 5.0 on the structural, morphological, optical and electrical properties of samples was investigated by XRD, SEM, UV–vis and Hall Effect measurements. The XRD spectra showed that the characteristic peak intensity of CZTS semiconductor increased with increasing pH value of the precursor solution. It was also observed that increased pH values resulted in a significant reduction in the amount of impurity phases of the films. The UV–vis studies revealed a significant increase in the optical absorption of thin films in the visible region as the pH value of the solution was increased. The band gap of the samples shifted from 2.0 to 1.38 eV by increasing the pH value. The electrical resistivity of the films was found to vary from 2.8×10⁻² to 3.1 Ω cm, depending on its pH value.     

化学气相沉积TiO2薄膜的XPS研究

通过XPS分析了TiO2薄膜的结构。薄膜是通过化学气相沉积的方法生长，有机源遇热发生分解，沉积在硅衬底上形成TiO2薄膜。XPS分析表明：所得TiO2薄膜含有Ti,C,O,Al,Si元素。各元素的电子结合能与理论值并无太大的偏移，说明通过化学气相沉积法制备的TiO2薄膜，纯度高，质量好，晶型为锐钛矿。     

薄Si膜对基底表面粗糙度的影响

利用ＺＹＧＯ光学干涉测量仪，散射积分测量法观测了光学元件表面均方根粗糙度．详细分析了薄Ｓｉ膜对基底均方根粗糙度的影响，由此认为薄膜并不总是复制基底表面的粗糙度，结果出现了薄膜降低表面粗糙度的现象．提出了一定厚度范围的薄Ｓｉ膜的表面粗糙度存在着一个稳定值的新设想．     

Study of photoelectret phenomenon and dark depolarization current in evaporated semiconductor films of CdS

The photoelectret properties of vacuum evaporated CdS films on Pyrex glass plate have been studied. The deposition conditions were controlled to obtain high resistivity CdS films (resistivity of the order of 10⁷ Ω cm). The photoelectret polarization was carried out by simultaneous application of electric field and white light illumination from tungsten lamp source. The polarization exhibits the linear dependence upon the polarizing voltage and polarizing time, with saturation effects for large values of these parameters. The polarization in films is found to be four orders of magnitude higher than the corresponding value in thick CdS crystals or powders. The dark depolarization current decay is very slow, and time for current, to decay to approximately half of its initial value varies between 1 and 8 min. This large decay time is correlated to the presence of deep trap levels in the CdS films. The study is of significance to improve the performance of thin film CdS devices.     

超声雾化喷涂工艺及优质二氧化锡透明导电薄膜的研究

报道了采用超声雾化喷涂工艺沉积优质掺杂二氧化锡透明导电半导体薄膜的实验成果 ,选用氟作为掺杂元素 ,通过改变掺杂量和工艺参数 ,可控制薄膜的方块电阻在 1 0 Ω/□以上的范围内变化 (40 0 nm膜厚 ) ,掺氟离子二氧化锡为 n型导电半导体 ,高浓度掺杂的二氧化锡薄膜光学透过率为 87%～ 90 % (采用 550 nm单色光源测透过率 )。用 X射线衍射及扫描电子显微镜分析 ,可获得该薄膜材料的微结构、表面形貌以及薄膜组成、掺杂百分含量。该成果为大规模生产优质二氧化锡透明导电薄膜 ,提供了有效、简单的方法和装置。     

Amorphous chromium silicide formation in hydrogenated amorphous silicon

The interaction between thin films of hydrogenated amorphous silicon and sputter-deposited chromium has been studied. Following deposition of the chromium films at room temperature, the films were annealed over a range of times and temperatures below 350°C. It was found that an amorphous silicide was formed only a few nanometers thick with the square of thickness proportional to the annealing time. The activation energy for the process was 0.55±0.05 eV. The formation process of the silicide was very reproducible with the value of density derived from the thickness and Cr surface density being close to the value for crystalline CrSi₂ for all films formed at temperatures ≤300°C. The specific resistivity of the amorphous CrSi₂ was ≈600 μΩ·cm and independent of annealing temperature.