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.     

退火对用PLD法制备ZnO薄膜的发光影响

用脉冲激光沉积(PLD)方法在Si(111)和蓝宝石衬底上制备的氧化锌薄膜,在不同的退火温度和不同的退火氛围中进行了退火处理.退火温度及退火氛围对ZnO薄膜的结构和发光特性的影响用X射线衍射(XRD)谱和光致发光谱进行了表征.实验结果表明,随着退火温度的提高,ZnO薄膜的压应力减小,并向张应力转化.在不同的退火温度退火...     

Effect of annealing on electrical properties of radio-frequency-sputtered ZnO films

We report on the electrical properties of ZnO films and devices grown on different substrates by radio-frequency magnetron sputtering. The films grown on c-plane sapphire were annealed in the range 800–1,000°C. The electron concentration increased with annealing temperature reaching 1.4×10¹⁹ cm^?3 for 1,000°C. Mobility also increased, however, reaching its maximum value 64.4 cm²/V · sec for 950°C anneal. High-performance Schottky diodes were fabricated on ZnO films grown on n-type 6H-SiC by depositing Au/Ni(300/300 Å). After annealing at 900°C, the leakage current (at ?5 V reverse bias) decreased from 2.2 × 10^?7 A to ～5.0 × 10^?8 A after annealing at 900°C, the forward current increased by a factor of 2, and the ideality factor decreased from 1.5 to 1.03. The ZnO films were also grown on p-type 6H-SiC, and n-ZnO/p-SiC heterostructure diodes were fabricated. The p-n diode performance increased dramatically after annealing at 950°C. The leakage current decreased from 2.0×10^?4 A to 3.0×10^?7 A at ?10 V reverse bias, and the forward current increased slightly from 2.7 mA to 3.9 mA at 7 V forward bias; the ideality factor of the annealed diode was estimated as 2.2, while that for the as-grown sample was considerably higher.     

Influence of substrate temperature and post deposition annealing on the properties of vacuum deposited ZnSe thin films

The effects of substrate temperature and post deposition annealing on the structural, optical and electrical properties of vacuum deposited ZnSe thin films are presented here. The chemical composition of the films varied drastically with substrate temperature which in turn caused changes in various properties of the films. The grain size of the films increased with substrate temperature and also after annealing. The electrical properties of the films were found to be varying as a function of chemical composition and grain size.     

Effect of phosphotungstic acid on the properties of pulse deposited ZnSe films

ZnSe films were pulse electrodeposited on conducting glass substrates with and without the addition of phosphotungstic acid. X-ray diffraction studies indicated the formation of single-phase cubic ZnSe. The films possessed low dislocation density. Addition of phosphotungstic acid resulted in films with nanocrystallites. The band gap of the films were found to increase for the films deposited with phosphotungstic acid due to the quantum size effects. Thickness of the films was higher for the films deposited with phosphotungstic acid compared to those deposited without acid. The films had a crystallite size of the order of 15 nm and a surface roughness of 1.8 nm. The films were found to possess a slight excess of Se as evident from the EDAX measurements.     

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。     

Influence of annealing on the structural,optical and electrical properties of indium oxide films deposited on c-sapphire substrate

Indium oxide (In₂O₃) films were prepared on Al₂O₃ (0001) substrates at 700 °C by metal-organic chemical vapor deposition (MOCVD). Then the samples were annealed at 800 °C, 900 °C and 1 000 °C, respectively. The X-ray diffraction (XRD) analysis reveals that the samples were polycrystalline films before and after annealing treatment. Triangle or quadrangle grains can be observed, and the corner angle of the grains becomes smooth after annealing. The highest Hall mobility is obtained for the sample annealed at 900 °C with the value about 24.74 cm²·V^-1·s^-1. The average transmittance for the films in the visible range is over 90%. The optical band gaps of the samples are about 3.73 eV, 3.71 eV, 3.70 eV and 3.69 eV corresponding to the In₂O₃ films deposited at 700 °C and annealed at 800 °C, 900 °C and 1 000 °C, respectively.     

Microwave annealing effects on ZnO films deposited by atomic layer deposition

Zinc oxide thin films deposited on glass substrate at 150°C by atomic layer deposition were annealed by the microwave method at temperatures below 500 °C.The microwave annealing effects on the structural and luminescent properties of Zn O films have been investigated by X-ray diffraction and photoluminescence.The results show that the MWA process can increase the crystal quality of Zn O thin films with a lower annealing temperature than RTA and relatively decrease the green luminescence of Zn O films.The observed changes have demonstrated that MWA is a viable technique for improving the crystalline quality of Zn O thin film on glass.     

Effect of sputter deposited Zn precursor film thickness and annealing time on the properties of Cu2ZnSnS4 thin films deposited by sequential reactive sputtering of metal targets

Cu₂ZnSnS₄ (CZTS) is made of earth abundant elements and also have suitable optical properties for solar cell applications. But, in phase diagram, CZTS exists in a narrow range of temperature and composition. Therefore, optimizing the elemental composition and annealing time is very important for obtaining phase pure CZTS. In this study, the effects of elemental composition and short annealing time on the structural and optical properties of reactively sputtered CZTS thin films are reported. Thin films were deposited by reactive sputtering of Cu: Sn (60:40 wt%), Sn and Zn targets sequentially in the presence of H₂S at room temperature. Amount of Zn precursor was varied by changing the sputter time for Zn. The films were rapidly annealed in inert atmosphere for varying time. The band gap of sample changed with change in the composition as well as annealing time. Sample with higher Zn content showed better crystallinity. With increase in the annealing time the crystallinity of samples improved. Sample annealed for 12 min at 550 °C was phase pure. Obtaining good quality film even for very short anneal time is the novelty of reactive sputtering method as all the elements are already mixed and short annealing is required only for crystal growth. Through detailed experiments, the optimum composition and annealing time required for the growth of phase pure CZTS has been established.     

Effects of annealing on the structural and optical properties of zinc sulfide thin films deposited by ion beam sputtering

We report the structural and optical properties of ZnS thin films fabricated by ion-beam sputtering. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results revealed a polycrystalline ZnS film with zinc blende phase as manifested by diffraction from the (111), (220) and (311) planes. Annealing resulted in the appearance of a metastable wurtzite phase with a concentration up to 26.6%. An energy bandgap, estimated from absorption spectra, was found to vary between 3.32 and 3.40 eV. The lower energy of this bandgap, as compared to bulk ZnS, is associated with the structural point defects along with mixed zinc blende and wurtzite phases of the polycrystalline ZnS films. Ion beam sputtering deposition can be used to tune the optical bandgap for potential applications in optoelectronic materials.     

（英）退火温度对电子束蒸发沉积硅薄膜结构和光学性能的影响

系统研究了退火温度对硅薄膜结构和光学性能的影响。通过电子束蒸发工艺制备硅薄膜,然后在氮气保护下对薄膜样品在200~500°C范围内进行退火处理。使用XRD、拉曼光谱、电子自旋共振和透射光谱测量等方法对薄膜样品进行了表征。结果显示,随着退火温度的升高,非晶硅薄膜结构有序度在短程和中程范围内得到改善,同时缺陷密度显著降低-。当样品在400°C退火后,消光系数k由6.14×10^-3下降到最小值1.02×10~3(1000 nm),这是由于此时硅薄膜缺陷密度也降到最低,约为沉积态薄膜的五分之一。试验结果表明,硅薄膜在适当的温度下退火可以有效地降低近红外区膜层的光学吸收,这对硅薄膜在光学薄膜器件研制中具有重要应用。     

退火过程对c轴择优取向的ZnO薄膜的光学性质的影响

利用溶胶凝胶法在石英衬底上采用旋涂法制备出ZnO薄膜,通过X射线衍射仪发现不同的退火温度对ZnO薄膜的择优取向有很大影响;通过紫外可见分光光度计和室温发光谱可以看出,制备的薄膜有很好的光学透过性和很强的紫外发光特性,而不同的退火温度对其光学性质有很大的影响。实验发现采用此种方法在650℃左右退火是一个合适的退火温度,结构特性和光学性质都相对较好;采用热分析方法可知ZnO将在375℃左右从非晶转向结晶状态,因而在常规ZnO薄膜制备方法中增加一步500oC的热处理将有助于提高ZnO薄膜的结晶质量。     

退火温度对AZO薄膜场发射性能的影响

以纯度为99.95%、Al₂O₃为2wt.%的 ZnO-Al₂O₃金属氧化物为溅射靶材,采用射频(RF)磁控溅射的方法,在玻璃衬 底上制备Al掺杂ZnO(AZO)薄膜,研究其场发射特性和导电性能,并分析了不同的退火温度 对AZO薄膜的形貌、导 电及场发射性能的影响。采用原子力显微镜(AFM)及X射线衍射(XRD)对AZO薄膜表面 形貌与结晶特性 进行测试的结果表明,随着退火温度的升高,AZO薄膜的表面粗糙度随之增大,AZO薄膜的结 晶度变好;场发射 性能研究的结果表明,AZO薄膜的开启电场随着退火温度增加呈先减小后增大的趋势,当 退火温度为300℃时, AZO薄膜样品粗糙度最大,场发射性能最好,开启场强为2.8V/μm, 发光均匀性较好,亮度达到650cd/m²,导电 性能最好,电阻率为5.42×10－4 Ω·cm。     

Investigation of oxygen annealing effects on RF sputter deposited SiC thin films

Amorphous silicon carbide films were deposited by RF sputtering technique using a SiC target. These films were annealed in dry oxygen ambient in the temperature range of 400–700 °C. Subsequently the films were characterized using X-ray photoelectron spectroscopy (XPS) to investigate the chemical composition at each annealing temperature. XPS indicated that increasing the anneal temperature results in a decrease in SiC phase, and an increase in SiO_x. Surface morphology of the oxidized films was characterized using atomic force microscope. Optical absorption studies indicated blue shifting effects as the annealing temperature was increased.     

Rapid thermal annealing of zirconia films deposited by spray pyrolysis

Zirconia (8 mol% yttria) (YSZ) amorphous layers were deposited by spray pyrolysis on Si oxidized substrates and crystallized by rapid thermal treatment in a home-made halogen lamps furnace. Uniform films were obtained by depositing up to six layers, followed by the thermal treatment. X-ray analysis showed that the cubic phase is obtained during the initial stage of the annealing process. No significant differences with increasing annealing time nor interaction between the YSZ film and the substrate were observed. Ionic conduction in air, with activation energies comparable to those of bulk YSZ ceramics, was observed. The electrical characteristics of the films make them suitable for microelectronics applications.     

Effect of annealing on physical properties of CBD synthesized nanocrystalline FeSe thin films

Nanocrystalline FeSe thin films were successfully prepared by solution growth method using ferric chloride and sodium selenosulphate as cationic and anionic precursors along with complexing agent oxalic acid. The thickness dependent physical properties of FeSe thin films prepared by varying deposition time are discussed. The FeSe films of thickness 161 nm were further annealed to investigate its impact on physical properties. The X-ray diffraction studies showed that, as deposited FeSe films are nano crystalline in nature and their crystallinity increases with thickness as well as with annealing temperature. The morphological studies showed that FeSe exhibits granular surface with channel like features at higher thickness. The electrical resistivity and thermo-emf measurements confirmed that, FeSe films are semiconducting in nature with P-type conductivity. The activation and band gap energies of FeSe films are found dependent on film thickness as well as on annealing temperature.     

磁场退火对FePt/Ag薄膜磁性能的影响

采用磁控溅射法室温沉积获得FePt/Ag薄膜,然后在500℃下,于真空磁退火炉中对薄膜进行退火处理。利用XRD和振动样品磁强计(VSM),研究了磁场退火对薄膜结构和磁性能的影响。结果表明,500℃零磁场退火获得了矫顽力为0.763 4 MA.m–1、平均晶粒尺寸21 nm的L10-FePt薄膜。磁场提供了FePt成核生长的驱动力,0.8 MA.m–1磁场退火后FePt的平均晶粒尺寸为26 nm,矫顽力增大至0.804 3 MA.m–1。非磁性Ag的掺杂可有效抑制磁性FePt晶粒的团聚生长。     

退火温度对WO3薄膜结构及气敏性能的影响

采用直流磁控溅射法制备了WO3薄膜,并在350~550℃时对薄膜进行退火处理,研究了退火温度对薄膜结构及气敏性能的影响。结果表明:退火前及350℃退火后的薄膜为非晶态,450℃和550℃退火后的薄膜为WO3–x型晶态;随退火温度的提高,薄膜厚度增加,晶粒度增大。550℃退火后薄膜的厚度,较450℃退火后薄膜厚30nm,晶粒度相差8nm;450℃和550℃退火后的薄膜,在150℃时对体积分数为0.05%的NO2的灵敏度接近于22。     

Effect of substrate bias on the properties of plasma deposited organosilicone (pp-HMDSN) thin films

Organosilicone thin films have been deposited by plasma polymerization (pp) in a plasma enhanced chemical vapor deposition (PECVD) system using hexamethyldisilazane (HMDSN:C6H19Si2N) as a monomer precursor, at different biases of the stainless-steel substrate holder. The substrate bias affected film thickness, surface morphology, chemical composition and photoluminescence (PL) emission. For a negatively biased substrate, it is found that the film thickness is the minimum, while the porosity and PL emission are the maximum. For a positively biased substrate, the thickness and the ratio of Si/N are the maximum which correspond to a blue shift of the PL emission in comparison with the case of non-biased grounded substrate. In addition, the characterization of the plasma using a single cylindrical Langmuir probe has been performed to obtain information about both the electron density and the positive ion energy, where it can be concluded that the ion energy plays a major role in determining film thickness.     

Effect of thermal annealing on optical and photoelectric properties of microcrystalline hydrogenated silicon films

The effect of thermal annealing in the temperature range T _a=300–600°C of films of microcrystal-line hydrogenated silicon (μc-Si:H) lightly doped with boron on the spectral dependences of the absorption coefficient (α) at photon energies hν=0.8–2.0 eV, dark conductivity (σ_d), and photoconductivity (Δσ_ph) was studied at room temperature. With increasing annealing temperature, a nonmonotonic variation of α (at hν<1.2 eV), σ_d, and Δσ_ph was observed. The data obtained are attributed to a change in the concentration of electrically active impurities and formation of defects, caused by hydrogen effusion and bond restructuring at high annealing temperatures.