ZnS薄膜沉积过程的基材效应

采用热蒸发及离子束辅助沉积技术制备了单层ZnS薄膜,研究了Si、Ge、K9及石英玻璃基材对薄膜沉积速率及光学特性的影响。采用椭偏法拟合了薄膜的厚度和折射率,分析了不同基材上沉积薄膜的色散特性。研究结果表明,薄膜的生长存在明显的基材效应,无论室温沉积、基温200℃,还是采用离子束辅助沉积,石英基材上均具有最高的沉积速率。室温沉积时,4种基材上薄膜的沉积速率差为3.3 nm/min,加热进一步扩大了这种差异(5.2 nm/min),而离子束辅助则在一定程度上缩小了这种差异(1.86 nm/min)。在室温下,石英基材上沉积的ZnS薄膜具有最低的折射率,其他几种基材上折射率差异不大。加热会使Si、Ge及K9玻璃上的折射率差异变大,与石英玻璃上薄膜折射率差异减小,离子源的使用则进一步缩小了这种差异。透射率光谱测试证实了这一结果。     

An orientation competition in yttria-stabilized zirconia thin films fabricated by ion beam assisted sputtering deposition

A previously found orientation competition in ion beam sputtered yttria-stabilized zirconia thin films was studied in detail. The effects of sputtering energy and deposition angle were analyzed in ion sputtered films without assisting ions bombardment. It is found that for normally deposited films, (001) and (011) orientations are favored at low and high sputtering energy respectively. For inclined substrate deposited films, as deposition angle increases, (001), (011) and (111) orientations are advantaged in turn. The results can be attributed to the in-plane energy exchange of deposition atom and adatoms. In ion beam assisting deposited YSZ films of low assisting ions energy and current, a (001) oriented biaxial texture is gradually induced as ion energy increased. In the case of ion beam assisted inclined deposition of 45°, (001) orientation is enhanced and two preferential in-plane orientations are found coexist.     

Post-nucleation phenomena in the Volmer-Weber mode of epitaxy

Two commonly used methods of depositing a thin film in vacuum are evaporation and sputtering. Evaporation has the advantage of rapid deposition in relatively high vacuum for non-refractory materials. Evaporated films are, however, liable to be weakly bonded to the substrate, because of the low arrival energy of the evaporant, unless effects such as chemical bonding occur. Sputtered films generally bond strongly but sputtering is a much slower deposition process than evaporation so that there may be a high density of contaminating inclusions. As charging also affects the sputtering process special techniques such as r.f. sputtering must be employed for insulating targets.A saddle-field ion source has been developed which operates with cold cathodes and without a magnetic field at pressures compatible with evaporation. Evaporated films deposited in the presence of a beam from this source exhibit the bonding properties of sputtered films. The beam contains a high proportion of energetic neutrals so that the method can be applied to both insulating and conducting substrates. The ion source is compact and can be installed generally in existing vacuum equipment. The source geometry can be varied to ensure that the area covered by the beam matches the deposition area.     

ZnS薄膜的溅射沉积及其XPS研究

用Ａｒ^＋束溅射沉积技术在ＨｇＣｄＴｅ表面实现了ＺｎＳ的低温沉积．用Ｘ射线光电子能借（ＸＰＳ）对上述ＺｎＳ薄膜以及热蒸发ＺｎＳ薄膜中的Ｚｎ、Ｓ元素的化学环境进行了对比实验研究．实验表明：离子束溅射沉积ＺｎＳ薄膜具有很好的组份均匀性,未探测到元素Ｚｎ、Ｓ的沉积．     

Compositional and structural studies of ion beam deposited high-Tc oxide films by SNMS and REM

Polycrystalline YBaCu-oxide films were prepared by argon or oxygen ion beam sputtering of ceramic superconducting targets at 1 keV on sapphire and SrTiO₃ substrates. The influence of the bombarding species, the substrate material and temperature, and the post-deposition annealing treatment on the film composition was investigated with secondary neutral mass spectrometry (SNMS). In particular, oxygen ion beam sputter deposition as well as argon beam deposition at high substrate temperatures were found to result in a comparable enahancement of the Y and Ba incorporation. REM studies showed that post-annealed films switched from epitaxially ordered to polycrystalline structures within a narrow range of film thicknesses around 8000Å.     

1.6 Composition and stress state of thin films deposited by ion beam sputtering

The ion beam sputtering technique offers several advantages over conventional sputtering systems. This technique operates at a lower pressure and substrate temperature than conventional sputtering. In addition, the angle of deposition which is easily varied with ion beam sputtering is essentially fixed in dc and rf diode sputtering. As a result of these advantages, many of the parameters which effect film stress, resistivity, and grain size can be varied independently.Several properties of ion beam sputtered Ni, Al, Ni₃Al and Au thin films have been evaluated as a function of ion beam current density, target material, and the angle and distance of the substrate from the target.The grain size and stress were found to vary with the angle of deposition. There is an apparent correlation between electrical resistivity and the oxygen content in the films. Both properties depend upon the grain size. The stress levels of the films are shown to be influenced by the oxygen content. These experimental results are discussed in light of models proposed to explain the origin of stress in thin films.     

The influence of deposition parameters on the optical properties and growth of ZnS films

A vacuum automatic ellipsometer was used to observe and reveal the effect of the rate of deposition on the structural irregularities of ZnS films during growth.The high accuracy and sensitivity of this instrument were exploited for measuring the refractive index of ZnS films prepared at various rates of deposition and substrate temperatures.     

Structure and electrical properties of ITO thin films deposited at high rate by facing target sputtering

High rate deposition of ITO thin films at a low substrate temperature was attempted by using a facing target sputtering (FTS) system. Deposition rate as high as 53 nm/min was realized on polycarbonate film substrate of 80-μm thickness. When the film was deposited at a deposition rate above 80 nm/min, polycarbonate film substrate was thermally damaged. The film deposited by FTS has much smaller compressive film stress than the film deposited by conventional magnetron sputtering. The film stress was reduced significantly by increasing the sputtering gas pressure and stress-free films can be obtained by adjusting the sputtering gas pressure. This may be mainly caused by the fact that bombardment by high energy negative oxygen ions to substrate surface during deposition can be completely suppressed in the FTS. Film structure and electrical properties changed little with substrate position, and uniform films were obtained by the FTS.     

10.4—12.5μm单层红外增透膜的研究

红外光学薄膜的种类不但少，而且机械强度较差，尤其在中红外波段更是如此。根据薄膜光学理论计算了ＺｎＳ／Ｇｅ／ＺｎＳ、ＣｄＴｅ／Ｇｅ／ＣｄＴｅ和ＺｎＳｅ／Ｇｅ／ＺｎＳｅ三种ＡＲＣ组合的反射率和透射率。详细分析研究了吸收和色散对ＺｎＳ／Ｇｅ／ＺｎＳ极值透射率和反射率以及极值波长的影响。计算结果表明，ＺｎＳ／Ｇｅ／ＺｎＳ组合的光谱特性最好，吸收和色散对薄膜的光谱特性有一定影响。相对而言ＺｎＳ薄膜的机械强度较好。在理论计算的基础上，利用离子束辅助沉积方法制备ＺｎＳ薄膜，检测分析了薄膜的光谱性能，考察了薄膜的耐久性。     

Optical and electrical properties of ZnO films prepared by high rate sputtering

A new compressed magnetic field (CMF) magnetron sputtering technique is described. The radiation damage undergone by the substrate during the deposition of ZnO films is determined from the capacitance-voltage characteristics of metal/ZnO/SiO₂/Si structures and etch-back metal/oxide/semiconductor structures. These characteristics are compared with those of films prepared by conventional d.c. sputtering and it is shown that the CMF magnetron sputtering technique produces films with very low radiation damage at a very high deposition rate (10 μm h^-1). The optical properties of the ZnO films were measured by investigating the propagation of an He-Ne laser beam in the waveguide mode. The propagation loss was less than 10 dB cm^-1.     

Ionized-cluster beam deposition and epitaxy

Film formation by ionized-cluster beam deposition and epitaxy is characterized by various processes including sputtering, substrate surface heating effects, ion implantation effects and adatom migration. These processes can be utilized to form films of good crystalline quality. The technology is applicable for the formation of various kinds of films such as metals, semiconductors and insulators. The films show unique characteristics which cannot be obtained by conventional methods. A general review of ionized-cluster beam deposition and epitaxy is given and its application to electron devices is described.     

利用脉冲直流磁控溅射制备ZnO:Al薄膜的研究

利用中频脉冲直流磁控溅射法制备了平面ZnO:Al(AZO)透明导电薄膜,研究了沉积压力、衬底温度和溅射功率对AZO薄膜光电性能、薄膜稳定性的影响.结果表明:在较低沉积压力、衬底温度及溅射功率下,可获得具有低电阻率、高透过率、高稳定性的AZO薄膜.     

Effect of Ion Bombardment on the Structure and Properties of Polycrystalline Chromium Films

Polycrystalline chromium films were fabricated by electron beam evaporation with concurrent bombardment using argon ions from an ion gun or by sputtering with substrate bias. The microstructure and composition of the films were characterized using TEM/EDS. It was found that the grain size/shape, porosity, and argon content of the films strongly depend on the deposition parameters such as bombardment ion current density, deposition rate, argon pressure and substrate bias. Film properties including residual stress, resistivity, and reflectance were measured. A correlation of deposition, structure, and properties is discussed.     

离子束溅射法制备YBa_2Cu_3O_(7-x)超导薄膜

采用 YBa_2Cu_3O_(7-x)靶材,用离子束溅射法在多种衬底上得到了接近化学计量的YBa_2Cu_3O_(7-x)单相超导薄膜。     

Fe3Si薄膜的制备和性能研究

介绍了Fe3Si的一些基本特性及Fe3Si薄膜的几种主要制备方法,重点介绍了分子束外延法中不同类型衬底、温度对Fe3Si薄膜形成的影响,并且分析了各种制备方法中的一些重要参数对薄膜结构及性质的影响。随着Fe3Si薄膜制备工艺的不断完善,Fe3Si薄膜将会成为一种性能优秀的自旋电子器件。     

Deposition of optical thin films by ion beam sputtering

The use of sputtering from diode or magnetron sources has been investigated thoroughly in the last few years in order to replace traditional evaporation methods for optical thin film deposition. The kinetic energy of sputtered materials, higher than that of evaporated atoms, is one of the most important causes of the superior adherence, hardness and mechanical stability of sputtered thin films. Present technology evolution is tending to develop new techniques, allowing higher and more controllable energies of materials impinging on the substrate. In the ion beam sputter deposition (IBSD) technique the working pressure in the deposition chamber may be lower than 10^-2 Pa, so thermalization of sputtered materials is avoided and the energies of depositing atoms are higher than in plasma sputtering, where thermalization takes place. This work describes the investigations carried out for realizing optical treatments by means of IBSD. The apparatus used for this study is described with details of the experiments carried out and the results obtained in the deposition of TiO₂, Y₂O₃, Al₂O₃, SiO₂ and ZnS. The films are characterized optically, mechanically and for the determination of the damage threshold from 1064 nm laser radiation.     

Properties of Reactive Magnetron Sputtered ITO Films without in-situ Substrate Heating and Post-deposition Annealing

1. Introductiontransparent conductive indium tin oxide (ITO)films have been extensively used in a variety of electronic and opto--electronic applications because oftheir high transmission in the visible range, high infrared (IR) reflection, and low electrical resistivity.A variety of deposition techniques have been appliedto fabricate ITO films such as CVD, spray pyrolysisand sputteringll'2]. However, sputtering is the mostextensively used technique especially in industry. Recelltly, targe…     

Sputter deposition of ZnS:Mn/SrS:Ce multilayered thin film white phosphor

A full color thin film electroluminescent (TFEL) display can be fabricated by using color filters in combination with a high efficiency ‘white’ phosphor, such as a thin film multilayered stack of ZnS:Mn and SrS:Ce (denoted ZnS:Mn/SrS:Ce). To date, deposition of these multilayers has been limited to vacuum evaporation techniques and atomic layer epitaxy, both of which require different substrate temperatures for growth of high quality ZnS:Mn and SrS:Ce. This repeated thermal cycling during multilayer deposition can adversely affect electroluminescent (EL) performance and manufacturability. Sputter deposition of ZnS:Mn and SrS:Ce produces high quality phosphors for a wider range of substrate temperatures. We have determined a common set of radio frequency (rf) sputter deposition parameters for ZnS:Mn and SrS:Ce that result in high performance, multilayered white phosphors for use in TFEL devices. The EL performance of our samples is comparable to the best performance reported for evaporated multilayered samples. The major improvement is that the rf sputtered ZnS:Mn and SrS:Ce layers were deposited at the same substrate temperature. We report on the effects of sputter deposition parameters on the resultant composition and morphology of ZnS:Mn and SrS:Ce thin films and multilayers. Their EL performance was evaluated and correlated to composition and morphology.     

The influence of substrate temperature and sputtering gas atmosphere on the electrical properties of reactively sputtered indium tin oxide films

Tin-doped indium oxide (ITO) films were prepared by d.c. magnetron sputtering of an In-Sn alloy target, and the influence of the sputtering gas atmosphere and substrate temperature on their electrical properties was studied.The conditions for the deposition of the transparent ITO films were divided into three regions by varying the sputtering gas pressure. The first region was characterized by a high efficiency of oxygen gas consumption for film formation and a high deposition rate. In the second region the as-deposited films contained slightly less than the stoichiometric amount of oxygen. The third region was characterized by a low efficiency of oxygen consumption and a low deposition rate. The ratio of the amount of oxygen consumed to the amount of oxygen admitted to the sputtering chamber was about 15% when films with resistivities as low as 6 × 10^-4Ω cm were prepared at the optimum oxygen partial pressure.In the case of metallic deposited in an oxygen-poor atmosphere the carrier mobility, which mainly depends on the crystal structure, increased and the carrier concentration, which depends on the number of oxygen vacancies and donor centres, decreased with increasing substrate temperature. The opposite results were obtained for films deposited in an oxygen-rich atmosphere. Well-defined grain growth was observed, particularly for metallic films deposited at high substrate temperatures, and this caused the low carrier mobility.Subsequent heat treatment improved the resistivity of films deposited at substrate temperatures below 100°C, mainly because of the increase in carrier mobility, but it had little effect on the resistivity of films deposited at substrate temperatures above 150 °C because the increase in carrier mobility was cancelled by the decrease in carrier concentration.     

Multilayer antireflective and protective coatings comprising amorphous diamond and amorphous hydrogenated germanium carbide for ZnS optical elements

To effectively protect and improve the transmittance of ZnS optical elements in the far infrared band, combined amorphous diamond (a-D) and amorphous hydrogenated germanium carbide (a-Ge_1−xC_x:H) films have been developed. The optical interference coatings were designed according to the layer optics theory. The a-D films, of which refractive index and film thickness were controlled by changing substrate bias and deposition time respectively, were deposited by filtered cathodic vacuum arc technology. The a-Ge_1−xC_x:H films were prepared by radio frequency sputtering technology. During this process their refractive index was modulated by changing the gas flow rate ratio and their film thickness was controlled by the flow rate ratio and deposition time. It has been shown that the combined films are superexcellent antireflective and protective coatings for ZnS optical elements.