射频磁控溅射中离子输运的计算机模拟

采用射频辉光放电等离子体壳层模型和蒙特卡罗法 ,模拟了射频磁控溅射镀膜中工作气体离子 (Ar+)的输运过程 ,得到了离子到达靶面时的入射能量、角度和位置。模拟结果 :对靶材溅射的离子主要来自于溅射坑上方的等离子体区域 ,初始离子的位置分布可通过靶材溅射坑的形貌拟合得到 ;离子的能量主要集中在壳层电压附近 ,离子大多数以垂直入射。模拟与实际相符 ,可用作进一步模拟离子对靶材溅射时的输入参数。     

射频磁控溅射中离子输运的计算机模拟

采用射频辉光放电等离子体壳层模型和蒙特卡罗法，模拟了射频磁控溅射镀膜中工作气体离子(Ar^ )的输运过程，得到了离子到达靶面时的入射能量、角度和位置。模拟结果：对靶材溅射的离子主要来自于溅射坑上方的等离子体区域，初始离子的位置分布可通过靶材溅射坑的形貌拟合得到；离子的能量主要集中在壳层电压附近，离子大多数以垂直入射。模拟与实际相符，可用作进一步模拟离子对靶材溅射时的输入参数。     

直流辉光和磁控增强放电等离子体的空间分辨发射光谱技术

光学发射光谱(OES)方法是等离子体诊断的有力工具之一,可以定量地给出等离子体的多种重要参数,如等离子体中的物种成分、粒子能态分布、激发温度、粒子相对密度等.本文介绍了一种用于电子回旋共振(ECR)微波等离子体磁控溅射靶附近的增强放电和直流辉光放电等离子体空间分辨诊断的发射光谱装置.其特点是光学收集系统的位置可以水平精细移动,因而可以对放电区域进行空间分辨发射光谱测量.作者利用这套装置对氩气的ECR微波等离子体和直流辉光放电等离子体进行诊断.在ECR微波等离子体的下游区内氩离子谱线的发射强度很弱,主要是高激发态原子的辐射.在磁共振增强放电区,离子谱线强度有所增加但仍比原子谱线弱,类似于直流辉光放电正柱区的光发射特性.     

适用于溅射等离子体的诊断方法

本文评述用于许多溅射装置上的,能够用来表示各种辉光放电等离子体特性的参数和能够用来测量那些参数的方法。本评述通常也适用于用在离子镀上的等离子体和激活等离子体的活性蒸发。目的是为薄膜专家们提供一个简单的综述和文献指南。重点放在负辉光型等离子体和光谱学以及静电探测器诊断技术上,因为这些方法对上述等离子体特别有效,而且在实验室中比较容易实现。通过测量氩负辉光中高能电子浓度,为解释绝对强度线发射的电晕放电提出指南。在上述静电探测器测量中叙述的情况是用来研究圆柱形和圆柱空心磁控管溅射源的。 工引富 等离子体测量…     

双辉渗金属放电效应及电极结构设计原理

介绍了双层辉光离子渗金属技术的基本原理和技术特点,源极、阴极及辅助阴极设计的基本原则,离子渗金属的两种放电模式及其产生的效应,总结了渗金属电极几何结构设计原理.双层辉光离子渗金属技术主要有3个技术特点:固体材料的阴极溅射、形成有利溅射和扩散的高温条件和增加等离子放电的空心阴极效应.其放电模式为:独立放电模式和空心阴极放电模式.源极和阴极设计原则依据双层辉光离子渗金属的特点和放电模式,为"仿形"原则.     

离子溅射磁控管装置的研究

本文介绍了对离子溅射磁控管装置中磁场强度和工作气体坛强对伏安特性和起辉电压影响的实验研究。分析了阳极放电层内发生的过程,并在此基础上得到与实验结果相当接近的解析表达式。 低温等离子体新的很有前途的应用之一是通过离子溅射各种材料的靶板制取薄膜,直到目前为止,这种方法由于缺少高效率的溅射装置(PC)而难以大规模推广应用。譬如:在直流二极管型PC中,用于溅射过程的能量不超过总能量的3%,即使在高频溅射时效率的提高也不超过两倍(1,2)。磁控管型PC出现之后,这种局面大为改观(3)。这种PC装置是在放电区间(<700伏)的低电压测工…     

直流氩气辉光放电的PIC/MCC模拟分析

辉光放电在微电子工业中的应用越来越广泛。为了研究直流辉光放电稳态等离子体的特性,采用粒子网格方法(PIC法)与Monte Carlo碰撞模型(MCC方法)相结合的方法(PIC/MCC方法)跟踪了带电粒子的运动过程,同时充分考虑了电子与中性粒子的弹性、电离碰撞,离子与中性粒子的弹性和电荷交换碰撞,模拟结果得到了直流辉光电离过程达到稳态后的电子离子的相空间分布,得到了放电过程中带电粒子的速度、能量的空间变化,同时对粒子进行统计平均,得到了空间中的电势和电场强度分布,模拟结果与实验和理论相符,对实验有一定的指导意义。     

第十九讲 真空溅射镀膜

<正>(接2015年第2期第80页)三极溅射的电流密度最高约2 m A/cm2,放电气压可为1~0.1 Pa,放电电压1 000~2 000 V,镀膜速率约为二极溅射的两倍。但由于热丝电子发射,难以获得大面积均匀的等离子区,不适于镀制大工件。在利用冷阴极辉光放电的溅射装置中,阴极本身又兼作靶、与此不同的是,三极(以及四极)等离子体溅射装置是在产生热电子的阴极和阳极之间产生弧柱放电,并维持弧柱放电等离子     

磁控溅射中等离子体电离机制的数值解析

以圆柱形磁控溅射装置为研究对象,下极板外接通电线圈使之产生的磁场,并在上、下极板间施加直流电场,研究电磁场作用下等离子体中电子、离子、中性粒子和亚稳态离子分布。研究以Fortran语言自主编程,对所建立的模型用有限差分方法数值模拟。研究表明:辉光放电起始,电离项为等离子体中离子的主要来源;随着辉光放电趋于平衡,由一次电离、激发态二次电离等组成的累积电离项成为等离子体中离子的主体。达到稳定电离后,电子受磁场约束集中分布于下极板附近,从而使被电离的离子也集中分布于下极板附近。在距下极板15~40 cm区间内,离子分布较均匀。     

一种新型溅射系统中的电子反射镜对放电特性的影响

本文对一种带有电子反射镜的溅射系统的放电特性进行了研究．并对几种不同形状的电子反射镜进行了研究比较。从中看到，圆筒形反射镜中心部分对电子的反射能力较弱，电子和离子容易逃离放电空间而影响等离子体的密度，并造成靶面刻蚀不均匀；同心圆筒型反射镜提高了中心部分反射电子的能力，明显提高了等离子体的密度，并使靶面刻蚀情况得到了改善；栅网型与盘香型反射镜都对电子有较强的反射能力，并能获得较高密度的等离子体；靶面刻蚀均匀。是比较理想的电子反射镜。由靶到电子反射镜之间的距离与靶的直径之比为１：１时，可以获得较高的放电电流。距离过大或过小都对放电不利。另外，磁场强对放电有很大影响，磁场强度的减弱会造成放电电流急剧下降。 由于此系统的磁力线与靶面垂直，所以对磁性材料与非磁性材料都能溅射。     

Effect of Enhanced Plasma Density on the Properties of Aluminium Doped Zinc Oxide Thin Films Produced by DC Magnetron Sputtering

Aluminum doped zinc oxide (AZO) thin films were prepared by DC magnetron sputtering at low substrate temperature. A coaxial solenoid coil was placed near the magnetron target to enhance the plasma density (Ji). The enhanced plasma density improved significantly the bulk resistivity (ρ) and its homogeneity in spatial distribution of AZO films. X-ray diffraction (XRD) analysis revealed that the increased Ji had inuenced the crystallinity, stress relaxation and other material properties. The AZO films deposited in low plasma density (LPD) mode showed marked variation in ρ (ranging from ～6.5×10?2 to 1.9×10-3 ·cm), whereas those deposited in high plasma density (HPD) mode showed a better homogeneity of films resistivity (ranging from ～1.3×10?3 to 3.3×10?3 ?·cm) at di?erent substrate positions. The average visible transmittance in the wavelength range of 500-800 nm was over 80%, irrespective of the deposition conditions. The atomic force microscopy (AFM) surface morphology showed that AZO films deposited in HPD mode were smoother than that in LPD mode. The high plasma density produced by the coaxial solenoid coil improved the electrical property, surface morphology and the homogeneity in spatial distribution of AZO films deposited at low substrate temperature.     

Study of the effect of plasma current density on the formation of titanium nitride and titanium oxynitride thin films prepared by reactive DC magnetron sputtering

Titanium nitride and titanium oxynitride films were deposited by varying the plasma current density from 10 mA/cm² to 40 mA/cm² using DC magnetron sputtering at constant gas flow rate and deposition time. Samples were characterized by Grazing Incidence X-Ray Diffraction, XPS, Nanoindentation and colorimetric analysis. Different coloured films like golden, blue, pink and green were obtained at different current densities. At lower current density (10 mA/cm²), golden coloured stoichiometric titanium nitride film was formed. At higher current densities (20, 30 and 40 mA/cm²), non stoichiometric Titanium oxynitride films of colour blue, pink and green were formed respectively. The thickness of the films increased with plasma current density from 43 nm to 117 nm. It was found that the colour variation was not only due to thickness of the film but also due to oxygen atoms replacing the nitrogen positions in TiN lattice. Hardness and Young Modulus of the films were found to decrease from 17.49 GPa to 7.05 GPa and 319.58 GPa-246.77 GPa respectively with increasing plasma current density. This variation of hardness and Young Modulus of the films can be speculated due to change in crystal orientation caused by oxygen incorporation in the films. The film resistivity increased from 16.46 × 10⁻⁴ to 3.28 × 10⁻¹ Ω cm for increasing plasma current density caused due to oxygen incorporation in the crystal lattice.     

Synthesis of high-density MgO films by a novel magnetron sputtering system

A novel magnetron sputtering system, which included simply designed two grids between target and substrate, was developed in our laboratory for the synthesis of high-density MgO films. In order to investigate the effect of grids assisted magnetron sputtering, MgO films were deposited by conventional magnetron, one grid assisted magnetron and two grids assisted magnetron. The saturated ion current density and Mg ion fraction in MgO discharges generated by grids assisted magnetron were increased in comparison with those obtained in conventional magnetron, which means that grids assisted magnetron led to the enhancement of plasma density. As a result of microstructure analysis, grids assisted magnetron produced a higher density MgO film with smoother surface compared to that obtained in conventional magnetron.     

The dependence of hardness on the density of amorphous alumina thin films by PECVD

Smooth, uniform and transparent aluminum oxide films were deposited at low temperature (≤ 500°C) by r.f. plasma enhanced chemical vapor deposition (PECVD) with AlCl₃, H₂ and CO₂ as the reactants. The measurements of mechanical and optical properties demonstrate a potential application of PECVD aluminum oxide film as an optical protective coating. The variation of film hardness and density with deposition parameters is apparent and shows a similar dependence while the composition stoichiometry is not so influenced. For amorphous thin films incorporating hydrogen and/or microvoid with no apparent variation on composition stoichiometry, the film hardness is dominated by density and a function near linear can be constructed as energy density is taken into account as an apparent character of hardness.     

An X-ray and neutron reflectometry study of ‘PEG-like’ plasma polymer films

Plasma-enhanced chemical vapour-deposited films of di(ethylene glycol) dimethyl ether were analysed by a combination of X-ray photoelectron spectroscopy, atomic force microscopy, quartz crystal microbalance with dissipation monitoring (QCM-D), X-ray and neutron reflectometry (NR). The combination of these techniques enabled a systematic study of the impact of plasma deposition conditions upon resulting film chemistry (empirical formula), mass densities, structure and water solvation, which has been correlated with the films'' efficacy against protein fouling. All films were shown to contain substantially less hydrogen than the original monomer and absorb a vast amount of water, which correlated with their mass density profiles. A proportion of the plasma polymer hydrogen atoms were shown to be exchangeable, while QCM-D measurements were inaccurate in detecting associated water in lower power films that contained loosely bound material. The higher protein resistance of the films deposited at a low load power was attributed to its greater chemical and structural similarity to that of poly(ethylene glycol) graft surfaces. These studies demonstrate the utility of using X-ray and NR analysis techniques in furthering the understanding of the chemistry of these films and their interaction with water and proteins.     

等离子体化学气相沉积金刚石膜过程中光发射谱和朗谬尔探针原位诊断

报道了利用光发射谱(OES)和朗谬尔探针对热阴极直流放电等离子体化学气相沉积金刚石薄膜的等离子体条件进行原位研究的部分结果,研究了几种过程参数变化中等离子体状态,并与金刚石膜的沉积相联系。当CH     

氧离子束流密度对Ta2O5薄膜的影响

利用氧离子辅助电子束蒸发沉积Ta2O5薄膜,在dd定氧离子能量的条件下研究了氧离子束流密度对Ta2O5薄膜的微观结构、化学计量比和漏电流密度的影响.利用原子力显微镜和X射线衍射仪对Ta2O5薄膜微观结构进行表征研究,发现随着离子束流密度增大,沉积的Ta2O5薄膜致密性提高,粗糙度下降,但薄膜一直保持非晶态;同时能谱仪测试的结果表明,薄膜中O/Ta比例逐渐提高,直至呈现富氧状态.测量了不同薄膜样品的漏电流密度和击穿场强,发现随着离子束流密度增大,薄膜漏电流密度显著降低,击穿场强提高.总之,提高氧离子束流密度能够明显改善Ta2O5薄膜的微观结构和电学性能.     

Plasma parameter analysis of Ag sputter deposition using cathodes with different magnetic flux densities

The effects of the magnetic flux density of the Ag sputter target surface on plasma parameters were investigated using the Langmuir probe system in this work. It was found that the electron energy and electron density near the substrate clearly decreased at a high magnetic flux density. In addition, the difference between plasma potential and floating potential (V_p−V_f) decreased at the high magnetic flux density relative to the potentials at the low magnetic flux density. The changes in plasma parameters could be interpreted as the result of many electrons being trapped in the neighborhood of the target surface (cathode sheath) at the high magnetic flux density; hence, the number of electrons in the space near the substrate is reduced. The Ag thin films exhibited low resistivity at a high magnetic flux density. The reduction in resistivity was attributed to the following factors: the low electron energy and electron density near the substrate; the low kinetic energy of positive argon ions; the low kinetic energy of argon atoms backscattered onto the target surface.     

Characterization of silicon oxide gas barrier films with controlling to the ion current density (ion flux) by plasma enhanced chemical vapor deposition

Silicon oxide gas barrier films were deposited on polyethylene terephthalate (PET) substrates by plasma enhanced chemical vapor deposition (PE-CVD) for applications to transparent barrier packaging. The barrier properties of the silicon oxide coated film were optimized by varying the bias conditions and input power in the radio frequency plasma. The plasma diagnostics, ion current density and substrate temperature were characterized by optical emission spectrometry (OES), an oscilloscope and thermometer, respectively. The coating properties were examined by Fourier transform infrared (FT-IR) spectroscopy and the water vapor transmission rate (WVTR). A high intensity of O and H ions and a high ion current density (ion flux) with a low temperature plasma process were found to be suitable for improving the barrier properties of the silicon oxide film coatings. The Si-O cage-like structure adversely affected the gas barrier properties of the deposited coating. The energy provided by ion bombardment (ion flux) can induce changes in the film density and composition similar to those that may occur by the increase in deposition temperature through rf bias. In addition, the film properties depend not only on a high ion current density (ion flux) and input power, but are also related to a silicon oxide film with a widely distributed planar ring size.     

Surface modifications of polymethylmetacrylate films using atmospheric pressure air dielectric barrier discharge plasma

In this paper, polymethylmetacrylate (PMMA) films are modified using an atmospheric pressure non-thermal plasma generated by a dielectric barrier discharge (DBD) in air. The DBD is generated in a plane-parallel reactor, which is driven by a μs pulse power supply with amplitude of up to 25 kV and repetition rate of 1 kHz, and the plasma generated shows homogeneous mode discharge characteristics verified by electrical measurements and light emission images with 0.5 ms exposure time. The treatment time ranging from 0 to 60 s and the discharge power density ranging from 11.62 to 30.83 W/m² are used to study the effects of discharge parameters on the surface treatment, and the surface properties of PMMA films are studied using contact angle and surface energy measurement, scanning electron microscopy (SEM), atomic force microscopy (AFM), fourier transformed infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS). The study shows that, after the plasma treatment, the surface of PMMA film is etched, and oxygen-containing polar groups are introduced into the surface. These two processes can induce a remarkable decrease in water contact and a remarkable increase in surface energy, and the surface properties of PMMA films is improved accordingly. It is shown that the improvement of hydrophobicity depends on the discharge power density and treatment time, and there is a saturation treatment time at each discharge power density. Increasing discharge power density can induce more effective treatment of PMMA films, and less treatment time is needed to achieve the same level of surface treatment by increasing the discharge power density. Because more oxygen-containing polar groups are created and more obvious etching is occurred on the PMMA surface at higher discharge power density.