铝掺杂对铜铟铝硒粉末微结构及光吸收影响的研究

铜铟铝硒(Cu(In_(1–x)Al_x)Se_2,CIAS)因其成本比铜铟镓硒低而成为目前备受关注的一种太阳电池材料。本文采用溶剂热法制备出含有不同铝掺入量的CIAS四元化合物粉末。利用XRD、SEM、XPS和紫外-可见光光吸收谱系统研究铝掺入对铜铟铝硒化合物的微观结构及光吸收的影响。研究表明铝掺杂对铜铟铝硒的微观结构有着显著影响,适当的铝掺入有利于铜铟铝硒晶体生长,当铝掺入比例x为0.4时,晶体在(112)晶面择优生长最为明显,并且随铝掺入量的增加可导致其禁带宽度增加,这有利于太阳电池优化设计。     

ITO:Mo透明导电薄膜的制备

利用通过固相烧结法得到的自制靶材,采用脉冲激光沉积法(PLD)在不同的衬底温度下沉积得到薄膜。通过XRD对它们的晶体结构进行分析,对薄膜断面进行扫描,测量其薄膜厚度。利用四探针法和霍尔效率测试仪,分别对薄膜的电阻率和载流子浓度及迁移率进行测量和分析。最后,用分光光度计对薄膜的透光率进行测量和分析,并计算了薄膜的禁带宽度。结果表明,在500℃下沉积的薄膜综合性能最好,电阻率可达2.611×10-4Ω.cm,透光率在90%以上,禁带宽度为4.29eV。     

Al-N共掺P型Zn0.95Mg0.05O薄膜的性能

利用直流反应磁控溅射法,以N2O为N掺杂源,用Al-N共掺技术制备了p型Zn0.95Mg0.05O薄膜.用X射线衍射分析(XRD)、Hall测试仪和紫外可见(UV)透射谱等研究方法对其晶体结构、电学性能和禁带宽度进行分析.XRD分析结果表明,Zn0.95Mg0.05O薄膜具有良好的晶格取向,Hall测试的结果所得p型Zn0.95Mg0.05O薄膜最低电阻率为58.5Ω·cm,载流子浓度为1.95×1017 cm-3,迁移率为0.546cm2/(V·s),UV透射谱所推出的薄膜禁带宽度中,纯ZnO,p型Zn0.95Mg0.05O和p型Zn0.9Mg0.1O分别为3.34,3.39和3.46eV,可以看出Mg在ZnO禁带宽度中起了调节作用.     

Al-N共掺p型Zn0.95Mg0.05O薄膜的性能

利用直流反应磁控溅射法,以N2O为N掺杂源,用Al-N共掺技术制备了p型Zn0.95Mg0.05O薄膜.用X射线衍射分析(XRD)、Hall测试仪和紫外可见(UV)透射谱等研究方法对其晶体结构、电学性能和禁带宽度进行分析.XRD分析结果表明,Zn0.95Mg0.05O薄膜具有良好的晶格取向,Hall测试的结果所得p型Zn0.95Mg0.05O薄膜最低电阻率为58.5Ω·cm,载流子浓度为1.95×1017 cm-3,迁移率为0.546cm2/(V·s),UV透射谱所推出的薄膜禁带宽度中,纯ZnO,p型Zn0.95Mg0.05O和p型Zn0.9Mg0.1O分别为3.34,3.39和3.46eV,可以看出Mg在ZnO禁带宽度中起了调节作用.     

溶胶-凝胶法制备掺镉ZnO薄膜及光学禁带研究

主要研究掺镉ZnO薄膜的光学禁带。采用溶胶-凝胶(Sol-Gel)旋转涂覆法,在Si(100)上生长掺镉ZnO薄膜,对薄膜的XRD分析表明,掺镉ZnO薄膜仍为六角纤锌矿结构,并沿c轴择优取向生长。通过实验优化出本工艺条件下的较佳参数:退火温度为800℃,x(Cd)=6%~8%;以普通玻璃为基片的透射光谱表明掺镉ZnO薄膜的禁带宽度约为3.22 eV,比纯ZnO晶体禁带宽度3.30 eV明显减小,适度掺镉可降低薄膜的光学禁带宽度。     

NiO薄膜的脉冲激光沉积及其结构和光学特性研究

利用脉冲激光沉积法在ITO玻璃衬底上制备了NiO薄膜,利用XRD、AFM对样品的晶体结构和表面形貌进行了表征,并对其透射光谱进行了测试,研究了衬底温度及脉冲激光能量对所制NiO薄膜的结构、形貌和光学特性的影响。结果表明:在脉冲激光能量为180 mJ、衬底温度为600~700℃条件下所制备的样品为沿(111)晶面择优取向生长的多晶NiO薄膜,薄膜结晶质量良好,表面颗粒排列均匀,可见光透射率较高,禁带宽度为3.40~3.47 eV。     

基于激光诱导击穿光谱技术的铜铟镓硒纳米薄膜的分析探测研究

铜铟镓硒薄膜中4种元素的含量比对薄膜的性能有非常大的影响。采用磁控溅射方法在不同工作气压下制备了铜铟镓硒薄膜,利用激光诱导击穿光谱(LIBS)技术实现了铜铟镓硒薄膜中Ga含量与(In+Ga)含量之比以及Cu含量与(In+Ga)含量之比的定量分析。分析了不同工作气压下制备的铜铟镓硒薄膜中元素谱线的强度,结果表明:IGa/I(In+Ga)与薄膜的禁带宽度是对应的,均随工作气压的增加而先增大后减小,当工作气压为2.0Pa时,获得了最大的薄膜禁带宽度;ICu/I(In+Ga)与能谱仪测得的浓度变化一致。LIBS技术能够实现薄膜中元素含量比例的快速检测,不同元素谱线强度的相对比值能够间接反映薄膜中元素含量的比值,验证了LIBS技术在薄膜分析方面的潜力,为优化磁控溅射制备铜铟镓硒薄膜的工作参数提供了方法和技术支持。     

射频磁控溅射法制备Cu_2ZnSnS_4薄膜

利用射频磁控溅射法在玻璃基片上制备了Cu2ZnSnS4(CZTS)薄膜,薄膜在室温下生长,再在Ar气氛中快速退火。通过X射线衍射、X射线电子能谱、原子力显微镜和吸收谱研究了退火温度对薄膜结构、组分、形貌和禁带宽度的影响。结果表明,所制备样品为Cu2ZnSnS4多晶薄膜,具有较强的沿(112)晶面择优取向生长的特点,薄膜组分均为富S贫Cu,样品表面形貌比较均匀。退火温度为350,400,450和500℃的薄膜样品的禁带宽度分别是1.49,1.53,1.51和1.46 eV。     

CIGS太阳能电池缓冲层ZnS薄膜的制备与表征

以硫酸锌、(NH4)2S2O3混合溶液为前驱体溶液,加入少量的柠檬酸钠和丙三醇为络合剂和分散剂,采用化学浴沉积法在玻璃衬底上成功制备了表面均匀的ZnS薄膜。研究了沉积时间和退火时间对ZnS薄膜质量的影响,并运用扫描电镜(SEM)、X射线衍射(XRD)、紫外-可见光光度计对薄膜进行分析和表征。结果表明:在沉积时间为90m in,退火温度为200℃时制得的薄膜性能较好,晶体结构为纤锌矿结构。制备的薄膜透过率(λ>400nm)约为80%,薄膜的禁带宽度约为3.75eV。通过添加少量的分散剂丙三醇可以改善ZnS薄膜质量。退火温度为300℃,薄膜表面形貌均匀致密。     

磁控溅射金属预置层后硒化法制备CuInSe_2薄膜工艺条件的优化

采用四因素四水平的正交实验法优化了磁控溅射金属预置层后硒化法制备CuInSe2 薄膜的工艺条件 .调节四个较为重要的影响因素 ,即Cu/In比、硒化时间、硒化温度和硒源温度制备得到 16个CuInSe2 样品 .用Hall效应仪对薄膜的电学性能进行了研究 ,并且通过XRD研究了薄膜的结构性能 .得到了制备具有较好电学性能的CuInSe2 薄膜的优化条件为 :Cu/In比 1 133,硒化温度 4 2 0℃ ,硒化时间 2 0min ,硒源温度 2 0 0℃ .在此优化条件下得到的薄膜Hall迁移率可以达到 3 19cm2 /(V·s) ,XRD结果表明薄膜中没有杂相存在 .     

Structural,optical and electrical properties of Cu2FeSnSe4 and Cu(In,Al)Se2 thin films

Cu-based semiconductors Cu₂FeSnSe₄ (CFTSe) and Cu(In, Al)Se₂ (CIAS) have been fabricated using radio-frequency magnetron sputtering combined with rapid thermal selenization processing. For CFTSe, the heating rate ranging from 60 to 150 °C/min results in a difference in structure, morphology and optical properties. Thin film exhibits a pure phase structure, smooth surface and a band gap of 1.19 eV as the heating rate elevated to 90 °C/min. Furthermore, the CFTSe thin film selenized at 90 °C/min own the smallest value of cell volume compared with the others samples, which represents a more stable structure. In terms of the other Cu-based material CIAS, three different selenization pressures, i.e., 1, 5 and 10 Torr, have been employed for CIAS preparation. Thin film transforms into single phase with dense morphology along with the pressure of 1 Torr. The diverse band gap of CIAS thin films from 1.34 to 2.18 eV attribute to two reasons: (i) the various Al content will affect the hybridization degree of Al–Se, and finally tunes the band structure, (ii) amounts of CuSe has a certain degree of effect on the band gap of the CIAS. In addition, the electrical properties of CFTSe and CIAS are also researched with the open circuit voltage (V_oc) of 94 and 365 mV, respectively, signifying potential applications of CFTSe and CIAS for the thin film solar cells.     

Transport properties of copper indium aluminum selenide thin films deposited by successive Ionic layer adsorption and reaction

Cu(InAl)Se₂ (CIAS) thin films have been prepared by successive ionic layer adsorption and reaction (SILAR) technique on well-cleaned glass substrates. The structure, composition, morphology, optical, electrical, and Hall effect studies of prepared thin films have been studied. X-ray diffraction studies confirmed the polycrystalline nature of the thin films with a chalcopyrite structure. Scanning electron microscopy studies revealed that the morphology of the prepared films was smooth, dense, uniform, and granular. Composition of various constituents such as Cu, In, Al, and Se in the CIAS films has been determined from energy dispersive x-ray analysis. Optical properties have been studied in detail from the transmittance spectra in the visible and near infrared region and the optical transition has been found to be direct and allowed with the band gap of around 1.16–1.50 eV. Electrical analysis helps to identify that in high temperature region the conductivity is attributed due to thermal excitation of the charge carriers from grain boundaries to the neutral region of the grains. Transport properties of CIAS thin films have been studied in the temperature range 298–398 K and the transport parameters are evaluated and reported in this paper in detail.     

基于纳米颗粒的铜锌锡硫硒薄膜制备

采用热注入法制备了Cu2ZnSnS4(CZTS)纳米颗粒,并形成高分散、稳定的"墨水",采用滴注方法形成CZTS前驱体薄膜。利用X射线衍射(XRD)、拉曼光谱(Raman)、透射电子显微镜(TEM)和紫外-可见光谱(UV-VIS)对CZTS纳米颗粒的晶体结构、表面形貌和带隙进行了表征。Raman数据显示合成的纳米颗粒为纯的CZTS,不存在ZnS和Cu2SnS3等杂相。傅里叶红外光谱(FTIR)和UV-VIS表明合成的CZTS纳米颗粒表面被油胺(OLA)包覆,并且其带隙为1.52 eV。对CZTS前驱体薄膜在硫化氢气氛和固态硒气氛中退火处理,得到铜锌锡硫硒(CZTSSe)薄膜。结果表明,经硫化氢处理后薄膜表面平整但CZTS晶粒并没长大,而经过固态硒处理后得到了结晶质量较好的CZTSSe薄膜。     

Effect of Ag in CdSe thin films prepared using thermal evaporation

It has been a general practice to dope thin films with suitable dopants to modify the properties of the films to make them more suitable for potential applications. When the dopant concentrations are low, they do not normally affect the structure and morphology of the films. However, it may lead to drastic changes in electronic properties of the films. This might result from the dopant getting incorporated into the lattice of the material of the films. Cadmium selenide is an important compound semiconductor material with an attractive energy band gap. The present work relates to an attempt made to dope CdSe thin films with silver. CdSe:Ag (1–5%) thin films were deposited on glass substrates at an optimized substrate temperature of 453 K using thermal evaporation technique. The grown films were analyzed using X-ray diffraction, scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDX) techniques. It is observed that undoped CdSe thin films and CdSe:Ag films have hexagonal structure. The grain size was found to increase marginally with an increase in the Ag concentration. The optical band gap of the films determined by optical transmission measurements agree with that of CdSe. Electrical conductivity is observed to increase from 10^–4 to 3.66 (Ω cm)^–1 on addition of silver. The variation of resistance with temperature indicates that the prepared films consist of CdSe and Ag existing as two separate phases coexisting and contributing individually to the resistivity of the films.     

Tuning the Properties of CZTS Films by Controlling the Process Parameters in Cost-Effective Non-vacuum Technique

Highly dispersive Cu₂ZnSnS₄ (CZTS) nanoparticles were successfully synthesized by a simple solvothermal route. A low cost, non-vacuum method was used to deposit CZTS nanoparticle ink on glass substrates by a doctor blade process followed by selenization in a tube furnace to form Cu₂ZnSn (S,Se)₄ (CZTSSe) layers. Different selenization conditions and particle concentrations were considered in order to improve the crystallinity and surface morphology; the annealing temperature was varied between 400°C and 550°C and the annealing time was varied between 5 min and 20 min in a selenium-nitrogen atmosphere. The influence of annealing conditions on structural, compositional, optical and electrical properties of CZTSSe thin films was studied. An improvement in the structural and surface morphology was observed with increasing of annealing temperature (up to 500°C). An enhancement in the crystallinity and surface morphology were observed for thin films annealed for 10–15 min. Absorption study revealed that the band gap energy of as-deposited CZTS thin film was approximately 1.43 eV, while for CZTSSe thin films it ranged from 1.15 eV to 1.34 eV at different annealing temperatures, and from 1.33 eV to 1.38 eV for different annealing times.     

金属离子掺杂纳米TiO2薄膜光阳极的性能研究

采用溶胶-凝胶法在玻璃衬底上制备TiO2多孔薄膜,掺杂不同功函数的金属离子制备M-TiO2纳米薄膜电极,XRD、AFM,UV-Vis检测M-TiO2结构、形貌和性能.结果表明:掺杂摩尔分数2%的金属离子没有改变TiO2的晶格结构,但其吸收峰在可见光区都发生明显的红移,禁带宽度降低,掺杂后的M-TiO2电极比没有掺杂的T...     

Investigation of the optical and structural properties of thermally evaporated cadmium sulphide thin films on polyethylene terephthalate substrate

Cadmium sulphide (CdS) thin films of different thicknesses ranging from 100 to 400 nm were prepared on polyethylene terephthalate (PET) substrates at room temperature by thermal evaporation technique in vacuum of about 3×10⁻⁵ Torr. The structural characterisation was carried out by X-ray diffraction (XRD). These studies confirm the proper phase formation of the cadmium sulphide structure. The root mean square (RMS) roughness of the films was measured using atomic-force microscopy. The root mean square roughness of the films increases as the film thickness increases. The energy gap of CdS on PET substrates was determined through the optical transmission method using an ultraviolet–visible spectrophotometer. The optical band gap values of CdS thin films slightly increase as the film thickness increases. The optical band gap energy was found to be in the range of 2.41–2.56 eV.     

Annealing and light effect on optical and electrical properties of ZnS thin films grown with the SILAR method

Zinc sulphide (ZnS) thin films were grown on glass substrates by the Successive Ionic Layer Adsorption and Reaction (SILAR) technique at room temperature and ambient pressure. Surface morphologies of grown films were characterized using scanning electron microscopy (SEM). The crystal structure and crystal size of the thin films were characterized by the X-ray diffraction (XRD) method and found that the films exhibit polycrystalline characterization. The optical absorption measurements were done as a function of the temperature at 10–320 K temperature range. Using absorption measurements, the band gap energies were calculated at 10 and 320 K, as 3.83 and 3.72 eV, respectively. The annealing temperature effect on optical band gap and the light effect on the electrical properties of ZnS thin films were investigated and it was found that the current increased with increasing light intensity. The annealed films were found have more resistance than the as-grown film.     

Effects of Cu incorporation on physical properties of ZnTe thin films deposited by thermal evaporation

The present paper reports on a systematic study of the Cu doping effect on the optical, electrical and structural properties of ZnTe:Cu (Cu=0, 6, 8, and 10 at%) thin films. Polycrystalline Cu-doped ZnTe thin films were deposited on glass substrates at room temperature by thermal evaporation. A detailed characterization of the Cu-doped ZnTe films were performed by X-ray diffraction (XRD), Spectrophotometry, Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy. XRD of the as-deposited Cu-doped ZnTe films belong to single-phase cubic structure of ZnTe with preferential orientation along (111) planes revealed minor effect of Cu content. The interference pattern in optical transmission spectra was analyzed to determine energy band gap, refractive index, extinction coefficient and thickness of the films. Wemple–DiDomenico and Tauc's relation were used for the determination and comparison of optical band gap values. The formation of ZnTe and Cu-doped ZnTe phase was confirmed by FT-IR. AC conductivity in a frequency range of 0–7 MHz has been studied for investigation of the carriers hoping dynamics in the films. Raman spectra indicated merely typical longitudinal optical (LO) phonon mode of the cubic structure ZnTe thin film at 194 cm⁻¹ because the excitation energy is well above of the optical band-gap of the material and exhibited a blue-shift from 194 to 203 cm⁻¹ with Cu which could be associated to the substitution of Zn atom with Cu at the lattice sites.     

氮气流量对磁控溅射AlN薄膜光学性能的影响

AlN薄膜因其具有优异的物理化学性能而有着广阔的应用前景,采用反应磁控溅射法在低温条件下制备AlN薄膜是近些年科研工作的热点.采用直流磁控溅射法,于室温下通入不同流量的氮气在p型硅(100)和载玻片衬底上沉积了AlN薄膜.利用傅里叶变换红外(FTIR)光谱仪、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和分光光度计等分析薄膜的组分、结构、形貌和光学性能.结果表明随着氮气流量的增加,AIN薄膜质量变好,N2流量为8 cma/min时制备的AlN薄膜为六方纤锌矿结构,在680 cm-1处具有明显的FTIR吸收峰,进一步说明成功制备了AlN薄膜.在300～ 900 nm的波长范围内,薄膜透过率最高可达94％;薄膜带隙随着氮气流量的增加而增大,最大带隙约为4.04 eV.