Investigation into the influence of direct current (DC) power in the magnetron sputtering process on the copper crystallite size

This paper discusses the influence of direct current (DC) power in the magnetron sputtering process on the crystallite size of the copper (Cu) thin films deposited on p-type silicon substrate at room temperature. X-ray diffraction (XRD) and Karl Suss four-point probe were employed to study the film crystallinity and conductivity, respectively. From the analysis on the XRD patterns, high DC power enhances the Cu film crystallinity with larger crystallite size, which is deduced using Sherrer's formula. The behavior of the electrical property of the Cu films complies with the trend of the film crystallinity with DC power, in which the film conductivity increases with increasing DC power. We attribute these phenomena to the enhanced surface diffusion mechanism of the adatom during the sputtering deposition process, which improves the microstructure of the Cu film.     

(100)取向AlN薄膜的制备及其压电性能研究

采用射频磁控溅射法,在Si(100)衬底(含Au导电层)上制备了(100)取向的AlN薄膜并研究了工作压强和溅射功率对制备的AlN薄膜性能的影响。利用X射线衍射仪(XRD)分析了薄膜结构特性,结果表明,在一定范围内,工作压强的增加和溅射功率的减小更有利于AlN(100)晶面择优取向的生长。利用压电力显微镜(PFM)对AlN薄膜的形貌和压电性能进行了表征,发现(100)择优取向的AlN薄膜的压电性主要表现在薄膜面内方向上。     

Silicon Nitride Films Deposited by RF Sputtering for Microstructure Fabrication in MEMS

In the present work, we report silicon nitride films deposited by a radio- frequency (RF) sputtering process at relatively low temperatures (<260°C) for microelectromechanical system (MEMS) applications. The films were prepared by RF diode sputtering using a 3-inch-diameter Si₃N₄ target in an argon ambient at 5 mTorr to 20 mTorr pressure and an RF power of 100 W to 300 W. The influence of the film deposition parameters, such as RF power and sputtering pressure, on deposition rate, Si-N bonding, surface roughness, etch rate, and stress in the films was investigated. The films were deposited on single/double-side polished silicon wafers and transparent fused-quartz substrates. To explore the RF-sputtered silicon nitride film as a structural material in MEMS, microcantilever beams of silicon nitride were fabricated by bulk, surface, and surface-bulk micromachining technology. An RF-sputtered phosphosilicate glass film was used as a sacrificial layer with RF-sputtered silicon nitride. Other applications of sputtered silicon nitride films, such as in the local oxidation of silicon (LOCOS) process, were also investigated.     

How to reduce the Al-texture in AlN films during film preparation

The preparation of aluminum nitrogen(AlN) film without Al texture is of great significance for the manufacture of highperformance surface acoustic wave(SAW) device.We research the process factors which bring Al into AlN film due to radio frequency(RF) magnetron sputtering system,and discuss how the process parameters influence the AlN thin film containing Al.In the research,it is found that the high sputtering power,the low deposition pressures and low partial pressure of Ar can lead to growing Al-texture during AlN thin film preparation,and the experiment also shows that filling the chamber with nitrogen gas can recrystallize a small amount of Al composition into AlN film during the annealing process in the high temperature environment.     

一种高性能氧化钒热敏薄膜的制备和应用

报道一种制备高性能氧化钒热敏薄膜的方法和其应用。采用反应磁控溅射薄膜沉积技术，通过改变氧化钒热敏薄膜沉积时溅射功率，从而调整钒原子在溅射出来之后接触到基片表面时的沉积速率，同时通过对设备进行改造升级，即在钒溅射腔腔外增加一个控制电源来精确控制溅射电压及氧气分压等参数来精确控制反应过程中电流密度，优化了氧化钒薄膜的制备工艺，制备出方块电阻为500 kΩ/□，电阻温度系数（TCR）为?2.7% K?1的氧化钒薄膜。实验测试结果表明，利用高性能氧化钒热敏薄膜制作的非制冷红外焦平面探测器，其噪声等效温差（NETD）降低30%，噪声降低28%，显著提升了非制冷焦平面探测器的综合性能。     

Thickness dependence of the structural and electrical properties of copper films deposited by dc magnetron sputtering technique

This paper addresses the influences of film thickness on structural and electrical properties of dc magnetron sputter-deposited copper (Cu) films on p-type silicon. Cu films with thicknesses of 130-1050 nm were deposited from Cu target at sputtering power of 125 W in argon ambient gas pressure of 3.6 mTorr at room temperature. The electrical and structural properties of the Cu films were investigated by four-point probe, atomic force microscopy (AFM) as well as X-ray diffraction (XRD). Results from our experiment show that the grain grows with increasing film thickness, along with enhanced film crystallinity. The root mean square (RMS) roughness as well as the lateral feature size increase with the Cu film thickness, which is associated with the increase in the grain size. On the other hand, the Cu film resistivity decreases to less than 5 μΩ-cm for 500 nm thick film, and further increase in the film thickness has no significant effects on the film resistivity. Possible mechanisms of film thickness dependent microstructure formation of these Cu films are discussed in the paper, which explain the interrelationship of grain growth and film resistivity with increasing Cu film thickness.     

磁控溅射工艺参数对Cu薄膜电阻率的影响

在确定Cu薄膜临界尺寸的基础上,选定基底温度、靶基距、溅射功率和工作气压为影响因素设计正交试验,研究了磁控溅射制备工艺对Cu薄膜电阻率的影响。研究结果表明:基底温度是影响薄膜电阻率的最主要因素,电阻率随着基底温度的升高而减小;在工艺条件为基底温度200℃、靶基距45 mm、溅射功率100 W、工作气压0.5 Pa时,所制薄膜的电阻率将会达到最小。最后,结合薄膜微观形貌对试验结论进行了分析,并对最佳工艺条件进行了实验验证。     

氧化铁镍薄膜的制备与表征

首先提出射频反应磁控溅射中薄膜沉积速率同O2流量和溅射功率关系的理论计算模型;其次根据这一理论计算模型,在O2/Ar气氛中,利用射频反应磁控溅射制备氧化铁镍薄膜;最后分别采用台阶仪、X射线衍射(XRD)、X射线光电子能谱(XPS)、电子扫描镜(SEM)和电化学工作站对薄膜进行了表征,并分析了在制备过程中O2含量、工作压强和溅射功率对薄膜的沉积速率、结构、组分和表面形貌的影响.实验验证了所提出的理论计算模型以及Ni3 的存在;得到了膜厚与晶型以及工作压强与形貌的关系;电化学测试结果为:在电流密度为8 mA/cm2时的过电势为284 mV.     

直流磁控溅射工艺参数对β-FeSi_2薄膜性能的影响

采用室温直流磁控溅射Fe-Si组合靶的方法,经过后续Ar气氛围退火,在单晶Si(111)衬底上生长β-FeSi2薄膜。研究了溅射功率、工作气压、Ar气流量、沉积时间等工艺参数对β-FeSi2薄膜结构特性及电学特性的影响,通过Raman、Hall、X射线衍射(XRD)等测试对其性能进行表征,对工艺参数进行了优化,在溅射功率为80W、工作气压为1.3Pa和Ar气流量为35SCCM时溅射沉积Fe-Si薄膜,不仅可以得到单一相的β-FeSi2,而且薄膜结晶质量较好。最终,在上述实验条件下制备得到的未掺杂的β-FeSi2薄膜是n型导电的,β-FeSi2薄膜中载流子浓度约为3.3×1016cm-3,迁移率为381cm2/Vs。     

溅射功率对Au与CdZnTe晶体接触结构和性能的影响

采用直流磁控溅射工艺,以Au为靶材在高阻半导体CdZnTe上制备导电薄膜.系统地研究了溅射功率对沉积速率、薄膜结构、组织形貌及接触性能的影响.结果表明,随溅射功率的增加沉积速率增大.I-V测试表明在高阻CdZnTe上溅射Au薄膜后不经热处理已具有良好的欧姆接触性能,溅射功率为100 W时的接触性能好于功率为40 W和70 W时的接触性能.     

Cu(In,Ga)Se2薄膜的制备及其表征

CuIn1-xGaxSe2(CIGS)为直接带隙半导体,其带隙宽度随In/Ga比而变化,且对可见光具有很高的吸收系数,是最有希望用于制作新一代高效、低成本薄膜太阳能电池的材料.采用直流溅射和后硒化工艺制备了系列CIGS薄膜,研究了溅射功率和衬底对CIGS薄膜的微结构和光学性质的影响.发现钼玻璃上溅射功率为50W,在55...     

LCP柔性基板的薄膜电阻制作技术

针对液晶聚合物(LCP)柔性基板高频电子封装应用需求,采用一种薄膜溅射工艺直接在LCP柔性基板上制作TaN薄膜电阻,研究不同等离子体预处理方式对LCP表面形貌和LCP表面薄膜金属膜层附着强度的影响,进一步研究溅射气压和氮气体积分数等参数对电阻性能的影响,考察LCP柔性基板上的TaN薄膜电阻精度及电阻温度系数(TCR),...     

The effect of carrier gas and H(hfac) on MOCVD Cu films using (hfac)Cu(1,5-COD) as a precursor

The deposition characteristics of metalorganic chemical vapor deposition (MOCVD) Cu using (hfac)Cu(1,5-COD)(1,1,1,5,5,5-hexafluro-2,4pentadinato Cu(I) 1,5-cyclooctadiene) as a precursor have been investigated in terms of carrier gas effects and adding H(hfac) to the carrier gas stream. Using hydrogen carrier gas led to a higher MOCVD Cu deposition rate and a lower film resistivity compared to an argon carrier gas system. Improvements in surface roughness of the MOCVD Cu films and a (111) preferred orientation texture were obtained by using hydrogen as a carrier gas. When a ligand such as H(hfac) was added to Ar carrier gas, the deposition rate was significantly enhanced. Moreover, H(hfac) added to both carrier gas streams led, to lower MOCVD Cu film resistivity. However, film adhesion was somewhat weak compared to that observed with the Ar or H₂ carrier gas system, probably due to the larger F content near the interface between the copper and the titanium-nitride film. In conclusion, smooth Cu films with a low resistivity can be obtained by manipulating the deposition conditions, such as carrier gas type and ligand addition. The deposition mechanism of MOCVD Cu is also discussed in the paper.     

Effect of processing parameter on structural,optical and electrical properties of photovoltaic chalcogenide nanostructured RF magnetron sputtered thin absorbing films

The aim of this work was to develop high quality of CuIn_1−xGa_xSe₂ thin absorbing films with x (Ga/In+Ga)<0.3 by sputtering without selenization process. CuIn_0.8Ga_0.2Se₂ (CIGS) thin absorbing films were deposited on soda lime glass substrate by RF magnetron sputtering using single quaternary chalcogenide (CIGS) target. The effect of substrate temperature, sputtering power & working pressure on structural, morphological, optical and electrical properties of deposited films were studied. CIGS thin films were characterised by X-ray diffraction (XRD), Field emission scanning electron microscope (FE-SEM), Energy dispersive X-ray spectroscopy (EDAX), Atomic force microscopy (AFM), UV–vis–NIR spectroscopy and four probe methods. It was observed that microstructure, surface morphology, elemental composition, transmittance as well as conductivity of thin films were strongly dependent on deposition parameters. The optimum parameters for CIGS thin films were obtained at a power 100 W, pressure 5 mT and substrate temperature 500 °C. XRD revealed that thin film deposited at above said parameters was polycrystalline in nature with larger crystallite size (32 nm) and low dislocation density (0.97×10¹⁵ lines m⁻²). The deposited film also showed preferred orientation along (112) plane. The morphology of the film depicted by FE-SEM was compact and uniform without any micro cracks and pits. The deposited film exhibited good stoichiometry (Ga/In+Ga=0.19 and In/In+Ga=0.8) with desired Cu/In+Ga ratio (0.92), which is essential for high efficiency solar cells. Transmittance of deposited film was found to be very low (1.09%). The absorption coefficient of film was ~10⁵ cm⁻¹ for high energy photon. The band gap of CIGS thin film evaluated from transmission data was found to be 1.13 eV which is optimum for solar cell application. The electrical conductivity (7.87 Ω⁻¹ cm⁻¹) of deposited CIGS thin film at optimum parameters was also high enough for practical purpose.     

BST铁电薄膜的制备及介电性能研究

通过射频磁控溅射法,采用高温溅射、低温溅射高温退火两种不同的工艺制备了钛酸锶钡（BST）薄膜。分析两种不同的工艺对BST薄膜的结构、微观形貌及介电性能的影响。采用X线衍射（XRD）分析了样品的微观结构。采用扫描电镜（SEM）和台阶仪分别测试了样品的微观形貌和表面轮廓。通过能谱分析（EDS）得到了薄膜均一性的情况。最后通过电容 电压（C V）曲线测试得到BST薄膜的介电常数偏压特性。结果表明,与低温溅射高温退火工艺制备的BST 薄膜相比,高温溅射制备的BST薄膜结晶度好,致密性高,表面光滑,薄膜成分分布较均一。因此,采用高温溅射得到的BST薄膜性能较好。在频率300 kHz时,采用高温溅射制备的BST薄膜介电常数为127.5~82.0,可调谐率为23.86%~27.9%。     

Improvement of the cell performance in the ZnS/Cu(In,Ga)Se2 solar cells by the sputter deposition of a bilayer ZnO : Al film

ZnS is a candidate to replace CdS as the buffer layer in Cu(In,Ga)Se₂ (CIGS) solar cells for Cd‐free commercial product. However, the resistance of ZnS is too large, and the photoconductivity is too small. Therefore, the thickness of the ZnS should be as thin as possible. However, a CIGS solar cell with a very thin ZnS buffer layer is vulnerable to the sputtering power of the ZnO : Al window layer deposition because of plasma damage. To improve the efficiency of CIGS solar cells with a chemical‐bath‐deposited ZnS buffer layer, the effect of the plasma damage by the sputter deposition of the ZnO : Al window layer should be understood. We have found that the efficiency of a CIGS solar cell consistently decreases with an increase in the sputtering power for the ZnO : Al window layer deposition onto the ZnS buffer layer because of plasma damage. To protect the ZnS/CIGS interface, a bilayer ZnO : Al film was developed. It consists of a 50‐nm‐thick ZnO : Al plasma protection layer deposited at a sputtering power of 50 W and a 100‐nm‐thick ZnO : Al conducting layer deposited at a sputtering power of 200 W. The introduction of a 50‐nm‐thick ZnO : Al layer deposited at 50 W prevented plasma damage by sputtering, resulting in a high open‐circuit voltage, a large fill factor, and shunt resistance. The ZnS/CIGS solar cell with the bilayer ZnO : Al film yielded a cell efficiency of 14.68%. Therefore, the application of bilayer ZnO : Al film to the window layer is suitable for CIGS solar cells with a ZnS buffer layer. Copyright © 2012 John Wiley & Sons, Ltd.     

直流磁控溅射制备非晶硅薄膜的研究

非晶硅薄膜（a-Si）是目前重要的光敏材料,在很多领域得到广泛应用。直流磁控溅射具有工艺简单．沉积温度低等优点,是制备薄膜的一种重要技术。采用直流磁控溅射工艺在玻璃基板上沉积薄膜,并对样品进行了退火处理。研究了沉积速率与溅射功率的关系。结果表明薄膜的沉积速率与溅射功率近似有线性关系。利用X射线衍射（XRD）对薄膜进行了分析鉴定,结果表明溅射的薄膜是非晶硅薄膜。利用扫描电子显微镜（SEM）对非晶硅薄膜的表面形貌进行了观察和分析,与X射线衍射测试的结果一致。所以．利用直流磁控溅射工艺能在常温下能快速制备出良好的非晶硅薄膜。     

生长功率对HgCdTe薄膜微观结构以及表面形貌影响

实验采用射频磁控溅射生长了HgCdTe薄膜,并利用台阶仪、XRD、原子力显微镜等现代分析手段对HgCdTe薄膜的生长速率、物相、表面形貌进行了研究。实验结果表明,随着溅射功率增大,其生长速率成线性增大,当溅射功率低于30w时,薄膜XRD衍射图谱上没有出现任何特征衍射峰,只是在2θ=23°附近出现衍射波包,材料具有明显的非晶态特征,当溅射功率高于30w时,XRD表现为多晶结构;AFM和SEM分析表明生长速率对HgCdTe薄膜表面粗糙度、形貌、形成机理等有直接影响,随着生长速率提高,薄膜表面粗糙度逐渐增大,且薄膜逐渐形成“迷津”结构。     

A statistical analysis of copper bottom coverage ofhigh-aspect-ratio features using ionized physical vapor deposition

Ionized physical vapor deposition (IPVD) is a new method for depositing metal into high-aspect-ratio features used as interconnects in microelectronic fabrication. It is similar to sputtering except that a portion of the metal flux to the substrate is ionized. We show how a high ionized-metal-flux fraction (IMFF) at the deposition location improves the bottom coverage of deposited metal films. To measure IMFF, a tool was developed, that biased the front surface of a microbalance crystal directly so as to repel ions. Cu IMFFs to the substrate of greater than 90 % along with deposition rates of 1000 Å/min can be achieved. A statistical model for both IMFF and total metal flux as a function of four control variables, chamber height, Ar pressure, ionizer power, and sputter power, was developed     

Effect of power variation on microstructure and surface morphology of HgCdTe films deposited by RF magnetron sputtering

Mercury cadmium telluride films were grown by the RF magnetron sputtering technique at different sputtering powers.In experiment,X-ray diffraction (XRD) and atomic force microscopy (AFM) have been used to characterize the microstructure of HgCdTe films.The experimental results showed that when the growth power increased,the growth rate of HgCdTe films increased; when the growth power was less than 30 W,the HgCdTe film deposited by RF magnetron sputtering was amorphous; when the growth power was more than 30 W,the films exhibited polycrystalline structure.Films deposited at different growth rates were found to have characteristically different formations and surface morphologies; as observed through AFM,the surface morphology is composed of longitudinal islands forming a maze-like pattern in the high deposition rate.AFM analysis also illustrated that a significant reduction in the areal density of large islands and characteristically smoother films was achieved using a low deposition rate.