Thickness-dependent optoelectronic properties of CuCr0.93Mg0.07O2 thin films deposited by reactive magnetron sputtering

CuCr_0.93Mg_0.07O₂ thin films were successfully deposited by DC reactive magnetron sputtering at 1123 K from metallic targets. The influence of film thickness on the structural and optoelectronic properties of the films was investigated. X-ray diffraction (XRD) results revealed that all the films had a delafossite structure with no other phases. The optical and electrical properties were investigated by UV–VIS spectrophotometer and Hall measurement, respectively. It was found that the optoelectronic properties exhibited a thickness-dependent behavior. The optical band gap and the average transmittance of the films showed a monotonous decrease with respect to the increase in thickness. The average transmittance in the visible region decreased from 67% to 47% as the thickness increased from ~70 nm to ~280 nm. Simultaneously, the conductivity of the films fell from 1.40 S∙cm⁻¹ to 0.27 S∙cm⁻¹. According to Haacke's figure of merit (FOM), a film with a maximum FOM value of about 1.72×10⁻⁷ Ω⁻¹ can be achieved when the thickness is about 70 nm (σ≈ 1.40 S·cm⁻¹ and T_av. ≈67%).     

Photoelectric properties of ITO thin films deposited by DC magnetron sputtering

As anti-reflecting thin films and transparent electrodes of solar cells,indium tin oxide（ITO） thin films were prepared on glass substrates by DC magnetron sputtering process.The main sputtering conditions were sputtering power,substrate temperature and work pressure.The influence of the above sputtering conditions on the transmittance and conductivity of the deposited ITO films was investigated.The experimental results show that, the transmittance and the resistivity decrease as the sputtering power increases from 30 to 90 W.When the substrate temperature increases from 25 to 150℃,the transmittance increases slightly whereas the resistivity decreases.As the work pressure increases from 0.4 to 2.0 Pa,the transmittance decreases and the resistivity increases.When the sputtering power,substrate temperature and work pressure are 30 W,150℃,0.4 Pa respectively,the ITO thin films exhibit good electrical and optical properties,with resistivity below 10^-4Ω·cm and the transmittance in the visible wave band beyond 80%.Therefore,the ITO thin films are suitable as transparent electrodes of solar cells.     

用直流磁控溅射法制备的ＩＴＯ薄膜的光电性能研究

用直流磁控溅射法将ＩＴＯ薄膜制备在玻璃基片上以作为太阳电池的透明电极。通过改变溅射功率、基片温度和工作气压来研究它们对所沉积的ITO薄膜的透过率和电导率的影响。实验结果表明：当溅射功率从30W增加到90W时,薄膜的透过率和电阻率都将减小;当基片温度从25℃ 增加到 150℃时,透过率稍微有点增大但电阻率减小;当工作气压从0.4Pa 增大到2.0Pa时,透过率减小,但电阻率增大。因此,在溅射功率为30W、基片温度为150℃、工作气压为0.4Pa 时,ITO薄膜有比较好的光电性能,其电阻率小于10-4 Ω•cm ,在可见光波段的透过率大于80%,适合于作为太阳电池的透明电极。     

衬底温度对磁控溅射生长HMGZO薄膜特性的影响

为适应高效Si基薄膜太阳电池对宽光谱透明导电 薄膜的需求,采用磁控溅射技术 生长了不同衬 底温度氢化作用下Ga和Mg共掺杂ZnO(HMGZO)透明导电氧化物(TCO)薄膜。研究了不同衬底温 度(200～280 ℃)对HMGZO薄膜 结晶特性及光电特性的影响。实验结果表明,制备的HMGZO薄膜均为具有六角纤锌矿结构的 多晶薄膜,呈 现(002)晶面择优生长。随着衬底温度的升高,薄膜中Mg含量逐渐增加,并且薄膜表面新型 锥状结构趋于 致密和均匀化。在各元素含量和结晶质量的共同影响下,其电阻率随着温度的升高从6．70×10－4 Ω·cm增加至7．63×10－4 Ω·cm。所有薄膜在可 见光区域(380～800 nm)的透过率均在80%以上,由于载流子共振吸收的作用,近红外区域的 透过率有所下降。MgO扩展带隙的作用和 Burstein-Moss(BM)效应的影响共同促进了薄膜光学带隙E_g展 宽,使得E_g达到了3.75 eV。当衬底温度为280 ℃ 时,薄膜方块电阻为4.91 Ω/sq,电阻率为7.63×10－4 Ω·cm,光电性能指数ΦTC值达0.022 Ω－1。     

射频磁控溅射法制备掺锆氧化锌透明导电薄膜

利用射频磁控溅射法在室温下制备出了掺锆氧化锌(ZnO∶Zr)透明导电薄膜。研究了溅射压强对ZnO∶Zr薄膜表面形貌、结构、光学和电学性能的影响。结果表明:ZnO∶Zr薄膜为六角纤锌矿结构的多晶薄膜,且具有c轴择优取向,溅射压强对薄膜电阻率有显著影响,压强为1.5Pa时,电阻率具有最小值1.77×10–3Ω·cm。所制备的ZnO∶Zr薄膜具有良好的附着性能,在可见光区平均透过率超过93%。     

Effect of thickness on optoelectrical properties of Nb-doped indium tin oxide thin films deposited by RF magnetron sputtering

Niobium-doped indium tin oxide （ITO:Nb） thin films are prepared on glass substrates with various film thicknesses by radio frequency （RF） magnetron sputtering from one piece of ceramic target material. The effects of thickness （60-360 nm） on the structural, electrical and optical properties of ITO: Nb films are investigated by means of X-ray diffraction （XRD）, ultraviolet （UV）-visible spectroscopy, and electrical measurements. XRD patterns show the highly oriented （400） direction. The lowest resistivity of the films without any heat treatment is 3.1×10^-4 Ω·cm^-1, and the resistivity decreases with the increase of substrate temperature. The highest Hall mobility and carrier concentration are 17.6 N·S and 1.36×10²¹ cm^-3, respectively. Band gap energy of the films depends on substrate temperature, which varies from 3.48 eV to 3.62 eV.     

Thermal conductivity of AlN thin films deposited by RF magnetron sputtering

Aluminum nitride (AlN) film, which is being investigated as a possible passivation layer in inkjet printheads, was deposited on a Si (1 0 0) substrate at 400 °C by radio frequency (RF) magnetron sputtering using an AlN ceramic target. Dependence on various reactive gas compositions (Ar, Ar:H₂, Ar:N₂) during sputtering was investigated to determine thermal conductivity. The crystallinity, grain size, and Al–N bonding changes by the gas compositions were examined and are discussed in relation to thermal conductivity. Using an Ar and 4% H₂, the deposited AlN films were crystalline with larger grains. Using a higher nitrogen concentration of 10%, a near amorphous phase, finer morphology, and an enhanced Al–N bonding ratio were achieved. A high thermal conductivity of 134 W/mk, which is nine times higher than that of the conventional Si₃N₄ passivation film, was obtained with a 10% N₂ reactive gas mixture. A high Al–N bonding ratio in AlN film is considered the most important factor for higher thermal conductivity.     

Enhanced photoluminescence properties of Cu-doped ZnO thin films deposited by simultaneous RF and DC magnetron sputtering

Copper (Cu)-doped ZnO thin films were grown on unheated glass substrates at various doping concentrations of Cu (0, 5.1, 6.2 and 7.5 at%) by simultaneous RF and DC magnetron sputtering technique. The influence of Cu atomic concentration on structural, electrical and optical properties of ZnO films was discussed in detail. Elemental composition from EDAX analysis confirmed the presence of Cu as a doping material in ZnO host lattice. XRD patterns show that the films were polycrystalline in nature with (002) as a predominant reflection of ZnO exhibited hexagonal wurtzite structure toward c-axis. From AFM analysis, films displayed needle-like shaped grains throughout the substrate surface. The electrical resistivity was found to be increased with increase of Cu content from 0 to 7.5 at%. Films have shown an average optical transmittance about 80% in the visible region and decreased optical band gap values from 3.2 to 3.01 eV with increasing of Cu doping content from 0 to 7.5 at% respectively. Furthermore, remarkably enhanced photoluminescence (PL) properties have been observed with prominent violet emission band corresponding to 3.06 eV (405 nm) in the visible region through the increase of Cu doping content in ZnO host lattice.     

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。     

直流磁控溅射法制备非晶态氧化钒薄膜光学特性研究

研究了直流反应磁控溅射工艺中衬底温度对氧化钒(V2O5)薄膜性能的影响,利用X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、X射线衍射(XRD)和紫外-可见光分光光度计(UV1700)分别对薄膜进行了表征.实验结果表明,除了组分和晶态,薄膜的形貌和光学性能受衬底温度的影响很大.随着衬底温度的升高,膜表面变得粗糙,膜厚减小.光学特性测试表明,当衬底温度从160℃升高到320 ℃,光学带隙从2.39 eV下降到2.18 eV.     

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.     

磁控溅射氧化钛薄膜在不同溅射温度下的光电性能研究

通过磁控反应溅射,在玻璃基底上制备了不同溅射温度下的氧化钛薄膜.通过对其光电性能的分析测试,探讨了溅射温度对氧化钛薄膜性能的影响.实验表明:低温溅射下,薄膜表面颗粒较小,结构较为疏松,高温溅射下,薄膜颗粒较大,薄膜表面颗粒出现团聚现象;随着溅射温度的升高,溅射速率减小;薄膜方阻减小,载流子浓度增大;溅射温度越高,薄膜在紫外可见光波段内透射越弱,光学带隙越小.     

退火处理对磁控溅射制备Ga掺杂ZnO薄膜性能的影响

采用磁控溅射法在普通玻璃上制备了Ga掺杂ZnO(GZO)薄膜,研究了退火处理对GZO薄膜组织结构、表面形貌及光电性能的影响,并利用扫描电子显微镜、X射线衍射仪、紫外分光光度计、四探针测试仪等对GZO薄膜的表面形貌、晶体结构、透光率及电阻率等进行测量与表征。结果表明:400~800℃退火对GZO薄膜的生长方式影响较小,所制薄膜均在(002)晶向沿c轴择优取向,退火温度对薄膜表面形貌影响较大,退火温度为600℃时,薄膜表面致密、平整,结晶质量最好,薄膜的透光率超过95%,电阻率最低为4.9×10~(-4)?·cm。     

不同退火条件对磁控溅射CdS薄膜性能的影响

采用磁控溅射法,在衬底温度300 ℃制备CdS薄膜,并选取370 ℃、380 ℃、390℃三个温度退火,获得在干燥空气和CdCl2源+干燥空气两种气氛下退火的CdS薄膜.通过研究热处理前后CdS薄膜的形貌、结构和光学性能表明,CdS薄膜在干燥空气中退火,晶粒度、表面粗糙度和可见光透过率变化不明显,光学带隙随退火温度的升高而增大; 在CdCl2源+干燥空气中退火,随退火温度的升高发生明显的再结晶和晶粒长大,表面粗糙度增大,可见光透过率和光学带隙随退火温度的升高而减小.分析得出: 上述性能的改变是由于不同的退火条件对CdS薄膜的再结晶温度和带尾态掺杂浓度改变的结果.     

Properties of V–Ce mixed-oxide thin films deposited by RF magnetron sputtering

Thin films of vanadium cerium mixed oxides are good counter-electrodes for electrochromic devices because of their passive optical behavior and very good charge capacity. We deposited thin films of V–Ce mixed oxides on glass substrates by RF magnetron sputtering under argon at room temperature using different power settings. The targets were pressed into pellets of a powder mixture of V₂O₅ and CeO₂ at molar ratios of 2:1, 1:1, and 1:2. For a molar ratio of 2:1, the resulting crystalline film comprised an orthorhombic CeVO₃ phase and the average grain size was 89 nm. For molar ratios of 1:1 and 1:2, the resulting films were completely amorphous in nature. Scanning electron microscopy images and energy-dispersive X-ray spectroscopy data confirmed these results. The optical properties of the films were studied using UV-Vis-NIR spectrophotometry. The transmittance and indirect allowed bandgap for the films increased with the RF power, corresponding to a blue shift of the UV cutoff. The average transmittance increased from 60.9% to 85.3% as the amount of CeO₂ in the target material increased. The optical bandgap also increased from 1.94 to 2.34 eV with increasing CeO₂ content for films prepared at 200 W. Photoacoustic amplitude (PA) spectra were recorded in the range 300–1000 nm. The optical bandgap was calculated from wavelength-dependent normalized PA data and values were in good agreement with those obtained from UV-Vis-NIR data. The thermal diffusivity calculated for the films increased with deposition power. For thin films deposited at 200 W, values of 53.556×10⁻⁸, 1.069×10⁻⁸, and 0.2198×10⁻⁸ m²/s were obtained for 2:1, 1:1, and 1:2 V₂O₅/CeO₂, respectively.     

MoNb薄膜直流磁控溅射制备及性能研究

以Mo-10%Nb(10%为粒子数分数)合金为靶材,采用直流磁控溅射法在钠钙玻璃基板上制备了MoNb薄膜。采用台阶仪、四探针电阻仪和AFM分别测试了Mo Nb薄膜的厚度、方块电阻及表面形貌。研究了功率密度、工艺气压及衬底温度对MoNb薄膜性能及其生长特性的影响。实验结果表明:功率密度增加2倍时,MoNb薄膜的沉积速率提升1.8倍,而电阻率降低2.3倍;工艺气压增大4倍时,MoNb薄膜的沉积速率提升1.5倍,其电阻率增大13倍。同时发现:衬底温度增加了135℃时,MoNb薄膜的表面粗糙度增加0.567nm,颗粒大小增加3.36nm。     

Electronic properties of zinc oxide thin films prepared by RF magnetron sputtering for varistor applications

ZnO thin films for varistor applications have been prepared by RF magnetron sputtering at a power of 0-1 kW using an argon pressure of 05 Pa. The films were polycrystalline with mean grain size typically 13 nm, and were preferentially oriented in the [002] direction. Optical absorption studies revealed a fundamental absorption edge at a wavelength of approximately 360 nm with a direct bandgap of 3.36 eV. van der Pauw measurements showed a decrease in resistivity from approximately 12ωm at thickness 50 nm to 0-5 ωm at thickness greater than 500 nm. Below 350 K the resistivity was essentially constant, while at higher temperatures an activation energy of approximately 0-2eV was observed, which was attributed to the effects of oxygen vacancies.     

Optical properties of amorphous carbon films deposited by magnetron sputtering of graphite

The thermal stability of amorphous carbon (a-C and a-C:H) has been studied by ellipsometry and spectrophotometry in the visible and near-UV range (1.5–5.6 eV). The dielectric function of amorphous carbon has been derived and analyzed using the Kramers-Kronig technique. The conventional analytical approach is shown to be insufficient for the analysis of thermally treated samples. The fundamental absorption edge is analyzed with respect to collective effects in nanoscale fragments of the graphite-like component of the amorphous carbon structure. Two types of graphite-like clusters contributing to the spectral dependence of the fundamental absorption edge and modified by thermal treatment are revealed.     

射频磁控溅射制备钛酸锶钡薄膜的研究进展

综述了射频磁控溅射制备钛酸锶钡(BST)薄膜的国内外研究动态,详细阐述了溅射工艺参数(电极、溅射气压、氧分压、温度)对BST薄膜微结构和电性能的影响,提出了射频磁控溅射制备BST薄膜中亟待解决的问题。     

Structure and optoelectrical properties of transparent conductive MGZO films deposited by magnetron sputtering

The transparent conductive Mg-Ga co-doped ZnO (MGZO) films were prepared by radio-frequency (RF) magnetron sputtering. The influence of substrate temperature on the structural and optoelectrical properties of the films is studied. The results show that all the films possess a preferential orientation along the (002) plane. With the increase of substrate temperature, the structure and optoelectrical properties of the films can be changed. When substrate temperature is 300 °C, the deposited film exhibits the best crystalline quality and optoelectrical properties, with the minimum micro strain of 1.09´10-3, the highest average visible transmittance of 82.42%, the lowest resistivity of 1.62×10-3 W?cm and the highest figure of merit of 3.18×103 W-1?cm-1. The optical bandgaps of the films are observed to be in the range of 3.342—3.545 eV. The refractive index dispersion curves obey the Sellmeier’s dispersion model. #$TABThis work has been supported by the National Natural Science Foundation of China (No.11504436), and the Fundamental Research Funds for the Central Universities (Nos.CZP17002 and CZW14019).#$TABE-mail:zyzhongzy@163.com