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a-Si/SiO2多量子阱材料制备及其晶化和发光 总被引:3,自引:0,他引:3
本文研究用等离子体增强化学气相淀积(PECVD)方法淀积SiO2和非晶硅(a-Si)时淀积速率和薄膜折射率与淀积条件的关系。选择合适的淀积条件制备了a-Si/SiO2多量子阱结构材料。用激光扫描退火方法使其晶化,当a-Si和SiO2层厚度分别为4nm和6nm时,形成了颗粒大小为3.8nm的硅晶粒。晶化后的样品在10K下可以观察到较强的光荧光发射,三个峰值波长分别为810、825和845nm. 相似文献
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利用脉冲激光淀积法在Pt/Ti/SiO2/Si衬底上制备了28mol%La掺杂钛酸铅薄膜.采用不同的淀积氧气压,并分析了其对薄膜微观结构和介电性能的影响.结果表明,在2Pa左右的气压下淀积的薄膜具有好的结晶度和介电系数.在频率为10kHz时28mol%La掺杂钛酸铅薄膜的介电系数达852,并且保持了较低的损耗.同时制备了其他La掺杂浓度的PbTiO3薄膜,发现它们也有类似的特点.对此作了定性解释.
关键词:
脉冲激光淀积
PLT薄膜
气压
介电增强 相似文献
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光纤马赫—陈德尔干涉型8波分超窄波分复用器的研制 总被引:9,自引:2,他引:7
报道了采用7个单模光纤马赫-陈德尔干涉仪进行三级串联而组成的8波分复用器,既保留了干涉型光纤波分复用器超窄波分复用间隔的优点,又消除了其复用路数少的缺点。文中介绍了这类波分复用器的原理、设计方法和制造技术。实验样品的使用波段为1.5μm,波长复用间隔为2.4nm,整个器件的附加损耗约为1.5dB。 相似文献
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采用低压MOCVD系统,在生长过程中使用SiNx原位淀积的方法产生纳米掩模,并 在纳米掩模上进行选区生长和侧向外延制备了GaN外延薄膜.使用拉曼光谱和光荧光的手段对 GaN外延膜中的残余应力进行了研究.研究发现,用SiNx原位淀积出纳米掩模后 ,GaN生长将由二维向三维转变,直到完全合并为止.利用拉曼光谱和光荧光谱分别研究了薄 膜中的残余应力,两者符合得很好;这种方法生长出的GaN薄膜的应力分布较传统的侧向外 延更加均匀;并且从中发现随着生长过程中SiNx原位淀积时间的增加,生长在 其上的GaN外延膜中的残余应力减小.这是因为,随着SiNx原位淀积时间的增加 ,SiNx纳米掩模的覆盖度也增大.因此侧向外延区的比例增大,残余应力随之减 小.
关键词:
GaN
x原位淀积')" href="#">SiNx原位淀积
拉曼
光荧光
残余应力 相似文献
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用X射线光电子能谱(XPS)研究了在室温和超高真空条件下金属Ti淀积在AlN陶瓷表面上的化学反应过程.在金属Ti淀积之前,从AlN陶瓷的能谱中的Ols和Al2P的结合能可以看到因是样品的主要杂质,而且样品表面部分的Al被氧化.当样品淀积了金属Ti以后,发现刚淀积上去的Ti是氧化状态,还发现在Ti淀积的同时则Nls在高结合能处(402和406eV)出现新峰.随着Ti淀积厚度的增加,Ti低结合能的成份在增加而Al的氧化成份逐渐增加,Nls高结合能处的峰(402和406eV)也逐渐增高,更进一步成为主导地.N在
关键词: 相似文献
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广泛用子光学多层膜的真空蒸发ZrO_2~-薄膜若用于多层增透膜则存在一个缺点,这个缺点是由薄膜的折射率随着厚度增加而降低的光学非均匀性产生的。为了改善ZrO_2~-膜的光学均匀性,在ZrO_2~-蒸发物中添加TiO_3~-和Y_2O_3,并研究了用电子束蒸发的淀职膜的晶体结构。添加TiO_2的淀积膜的光折射率几乎是均匀的,薄膜的结构是不定形的;添加Y_2~-O_3~-的淀积膜显示出相当低的光学不均匀性和稳定的立方晶构造。通过适当添加Ti_2~-和Y_2~-O_3得到了用于多层膜的最适宜的ZrO_2~-膜;这种膜具有好的光学均匀性及足够的和可变的折射率,增加了硬度,并具有可靠的重复性。此外,从一种蒸发料片反复蒸发的薄膜的X射线衍射和X射线荧光分析的结果,推测了ZrO_2~-淀积膜的不均匀性的原因。 相似文献
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微缺陷对薄膜滤光片环境稳定性的影响 总被引:4,自引:2,他引:2
用热蒸发方法沉积了薄膜滤光片.并将样品分别在去离子水中浸泡10天和30天.通过分光光度计、光学暗场显微镜、及扫描电子显微镜等多种测试手段,对诱导透射滤光片在潮湿环境下的稳定性进行了研究.实验发现,在潮湿环境下滤光片产生的膜层分离都是从薄膜中微缺陷点处开始发生和发展的,微缺陷是影响滤光片环境稳定性的重要原因之一,其中杂质和针孔是滤光片中两种最常见的微缺陷.EDS能谱分析进一步表明,薄膜中杂质缺陷成分即为Al2O3膜料本身,所以不能推测,薄膜沉积中的喷溅可能是微缺陷产生的根本原因,抑制喷溅可以有效提高薄膜滤光片的环境稳定性.最后还用扩散理论对微缺陷引起滤光片失效的机理进行了分析. 相似文献
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确定薄膜厚度和光学常数的一种新方法 总被引:20,自引:7,他引:13
借助于不同的色散公式,运用改进的单纯形法拟合分光光度计测得的透过率光谱曲线,来获得薄膜的光学常数和厚度。用科契公式分别对电子束蒸发的TiO2和反应磁控溅射的Si3N4,以及用德鲁特公式对电子束蒸发制备的ITO薄膜进行了测试,结果表明测得的光学常数和厚度,与已知的光学常数以及台阶仪测得的结果具有很好的一致性。这种方法不仅简便,而且不需要输入任何初始值,具有全局优化的能力,对厚度较薄的薄膜也可行。采用不同的色散公式可以获得各种不同薄膜的光学常数和厚度,这在光学薄膜、微电子和微光机电系统中具有实际的应用价值。 相似文献
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电子束蒸发和离子束溅射HfO_2紫外光学薄膜 总被引:1,自引:0,他引:1
HfO2薄膜在紫外光学中具有十分重要的地位,不同方法制备的HfO2薄膜特性不同,可以满足不同的实际应用需求。本文分别利用电子束蒸发和离子束溅射方法制备了用于紫外光区域的HfO2薄膜,并对薄膜的材料和光学特性进行了表征与比较。通过对单层HfO2薄膜的实测透射和反射光谱进行数值反演,得到了HfO2薄膜在230~800 nm波段的折射率和消光系数色散曲线,结果表明两种方法制备的HfO2薄膜在250nm的消光系数均小于2×10-3。在此基础上,制备了两种典型的紫外光学薄膜元件(紫外低通滤波器和240nm高反射镜),其光谱性能测试结果表明,两种不同方法制备的器件均具有较好的光学特性。 相似文献
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射频磁控反应溅射氮氧化硅薄膜的研究 总被引:1,自引:0,他引:1
利用SiOxNy薄膜光学常数随化学计量比连续变化的特性,给出了制备折射率连续可调的SiOxNy薄膜的实验条件。用磁控反应溅射法制备了不同氮氧比的SiOxNy薄膜。研究了不同气流比率条件下薄膜光学常数、化学成分及溅射速率等的变化。用UV-VIS光谱仪测试了透射率曲线,利用改进的单纯型法拟合透射率曲线计算得到了折射率和消光系数。测试了红外傅立叶光谱(FTIR)曲线和X光光电子能谱(XPS)分析了薄膜成分的变化。实验表明薄膜特性与N2/O2流量比率密切相关,通过控制总压和改变气体流量比可控制SiOxNy薄膜的折射率n从1.92到1.46连续变化,应用Wemple-DiDomenico模型计算出光子带隙在6.5eV到5eV之间单调变化。 相似文献
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Influence of Concentration of Vanadium in Zinc Oxide on Structural and Optical Properties with Lower Concentration 下载免费PDF全文
ZnO films doped with different vanadium concentrations are deposited onto glass substrates by dc reactive magnetron sputtering using a zinc target doped with vanadium. The vanadium concentrations are examined by energy dispersive spectroscopy (EDS) and the charge state of vanadium in ZnO thin films is characterized by x-ray photoelectron spectroscopy. The results of x-ray diffraction (XRD) show that all the films have a wurtzite structure and grow mainly in the c-axis orientation. The grain size and residual stress in the deposited films are estimated by fitting the XRD results. The optical properties of the films are studied by measuring the transmittance. The optical constants (refractive index and extinction coefficient) and the film thickness are obtained by fitting the transmittance. All the results are discussed in relation with the doping of the vanadium. 相似文献
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Fabrication of broadband antireflection coatings using broadband optical monitoring mixed with time monitoring 下载免费PDF全文
Multi-layer optical coatings with complex spectrum requirements, such as multi-band pass filters, notch filters, and ultra-broadband antireflection coating, which usually contain very thin layers and sensitive layers, are difficult to be fabricated using a quartz crystal monitoring method or a single wavelength optical monitoring system(SWLOMS). In this paper, a broadband antireflection(AR) coating applied in the wavelength range from 800 nm to 1800 nm was designed and deposited by ion beam sputtering(IBS). Ta_2O_5 and Si O_2 were chosen as high and low refractive index coating materials,respectively. The optimized coating structure contains 9 non-quarter-wave(QW) layers totally with ultra-thin layers and sensitive layers in this coating stack. In order to obtain high transmittance, it is very important to realize the thickness accurate control on these thin layers and sensitive layers. A broadband optical monitoring mixed with time monitoring strategy was successfully used to control the layer thickness during the deposition process. At last, the measured transmittance of AR coating is quite close to the theoretical value. A 0.6% variation in short wavelength edge across the central 180 mm diameter is demonstrated. A spectrum shift of less than 0.5% for 2 continuous runs is also presented. 相似文献
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Effects of the ion-beam voltage on the properties of the diamond-like carbon thin film prepared by ion-beam sputtering deposition 下载免费PDF全文
《中国物理 B》2015,(6)
Diamond-like carbon(DLC) thin film is one of the most widely used optical thin films.The fraction of chemical bondings has a great influence on the properties of the DLC film.In this work,DLC thin films are prepared by ion-beam sputtering deposition in Ar and CH4 mixtures with graphite as the target.The influences of the ion-beam voltage on the surface morphology,chemical structure,mechanical and infrared optical properties of the DLC films are investigated by atomic force microscopy(AFM),Raman spectroscopy,nanoindentation,and Fourier transform infrared(FTIR) spectroscopy,respectively.The results show that the surface of the film is uniform and smooth.The film contains sp2 and sp3hybridized carbon bondings.The film prepared by lower ion beam voltage has a higher sp3 bonding content.It is found that the hardness of DLC films increases with reducing ion-beam voltage,which can be attributed to an increase in the fraction of sp3 carbon bondings in the DLC film.The optical constants can be obtained by the whole infrared optical spectrum fitting with the transmittance spectrum.The refractive index increases with the decrease of the ion-beam voltage,while the extinction coefficient decreases. 相似文献
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Optical properties of hexagonal boron nitride thin films deposited by radio frequency bias magnetron sputtering 下载免费PDF全文
The optical properties of hexagonal boron nitride (h-BN) thin films
were studied in this paper. The films were characterized by Fourier
transform infrared spectroscopy, UV--visible transmittance and
reflection spectra. h-BN thin films with a wide optical band gap Eg (5.86 eV for the as-deposited film and 5.97 eV for the
annealed film) approaching h-BN single crystal were successfully
prepared by radio frequency (RF) bias magnetron sputtering and
post-deposition annealing at 970~K. The optical absorption behaviour
of h-BN films accords with the typical optical absorption
characteristics of amorphous materials when fitting is made by the
Urbach tail model. The annealed film shows satisfactory structure
stability. However, high temperature still has a significant
effect on the optical absorption properties, refractive index n,
and optical conductivity σ of h-BN thin films. The
blue-shift of the optical absorption edge and the increase of Eg probably result from stress relaxation in the film under high temperatures. In addition, it is found that the refractive index
clearly exhibits different trends in the visible and ultraviolet regions.
Previous calculational results of optical conductivity of h-BN
films are confirmed in our experimental results. 相似文献
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Tikhii A. A. Nikolaenko Yu. M. Zhikhareva Yu. I. Zhikharev I. V. 《Optics and Spectroscopy》2020,128(10):1667-1670
Optics and Spectroscopy - The results of studying the optical transmission and X-ray diffraction spectra of thin In2O3 films obtained by DC magnetron sputtering on Al2O3 (012) substrates are... 相似文献