Deposition of Aluminium Oxide Films by Pulsed Reactive Sputtering

Pulsed reactive sputtering is a novel process used to deposit some compound films,which are not deposited by traditional D.C.reactive sputtering are presented.The hysteresis phenomenon of the sputtaring voltage and deposition rate with the change of oxygen flow during sputtering process are discussed.     

直流反应溅射制备ZnO：Al透明导电薄膜

本对直流反应溅射法制备ZnO:Al薄膜的工艺作了具体分析，探讨了氧分压、Al含量、溅射功率和靶基距等对ZnO:Al薄膜的电学、光学性能的影响。     

D.c. properties of ZnO thin films prepared by r.f. magnetron sputtering

In the development of ZnO-based varistors the electrical properties of ZnO/Bi₂O₃ junctions and of the two individual oxides are being investigated. Following our recent work on a.c. conductivity in Al---ZnO---Al sandwich structures we currently report d.c. measurements. The structures were prepared by r.f. magnetron sputtering in an argon/oxygen mixture in the ratio 4:1. Capacitance-voltage data confirm that the Al/ZnO interface does not form a Schottky barrier and measurements of the dependence of capacitance on film thickness indicate that the relative permittivity of the films is approximately 9.7. With increasing voltage the current density changed from an ohmic to a power-law dependence with exponent n≈3. Furthermore measurements of current density as a function of reciprocal temperature showed a linear dependence above about 240 K, with a very low activation energy below this temperature consistent with a hopping process. The higher temperature results may be explained assuming a room-temperature electron concentration n₀ and space-charge-limited conductivity, dominated by traps exponentially distributed with energy E below the conduction band edge according to N = N₀exp(−E/kT_t), where k is Boltzmann's constant. Typical derived values of these parameters are: n₀ = 7.2 × 10¹⁶ m⁻³, N₀ = 1.31 × 10⁴⁵ J⁻¹ m⁻³ and T_t = 623 K. The total trap concentration and the electron mobility were estimated to be 1.13 × 10²⁵ m⁻³ and (5.7−13.1) ×10⁻³m²V⁻¹s⁻¹ respectively.     

Effects of Substrate Temperature on Properties for Transparent Conducting ZnO:A1 Films on Organic Substrate Deposited by r.f. Sputtering

［1］W.S.Lan and S.J.Fonash: J. Elec. Mat., 1987, 141,16. ［2］Abhai Mansingh and C.V.R.Vasant Kumar: Thin Solid Films, 1988, 167, Lll. ［3］T.Karasawa and Y.Miyata: Thin Solid Films, 1993,223, 135. ［4］Bi-Shiou Chiou and Shu-Ta Hsieh: Thin Solid Films,1993, 229, 146. ［5］A.Mukhejee: Vacuum, 1989, 39(6), 537. ［6］T.L.Yang, D.H.Zhang, J.Ma, Y.Chen and H.L.Ma:Thin Solid Films, 1998, 326, 60. ［7］B.Cullity: Elements of X-ray Diffraction, AddisonWesley, London, 1959, 99. ［8］D.H.Zhang and D.E.Brodie: Thin Solid Films, 1992,213, 109. ［9］H.L.Ma, D.H.Zhang, P. Ma, S.Z.Win and S.Y.Li: Thin Solid Films, 1995, 263, 105. ［10］H.L.Ma, D.H.Zhang, S.Z.Win, S.Y.Li and Y.P.Chen:Solar Energy Materials and Solar Cells, 1996, 40, 371. ［11］D.H.Zhang and H.L.Ma: Appl. Phys. A, 1996, 62,487.     

Effects of Substrate Temperature on the Properties of Mo-doped ZnO Films Prepared by RF Magnetron Sputtering

Transparent conducting molybdenum-doped zinc oxide (MZO) films were successfully prepared by radio frequency (RF) magnetron sputtering method on glass substrates under different substrate temperatures. The nature of MZO film is polycrystalline with hexagonal structure and a preferred orientation along c-axis. With increasing substrate temperature from room temperature to 400°C, the crystallinity of the films is deteriorated and the resistivity increases sharply due to both the decrease of carrier concentrat...     

Transparent Conducting ZnO:A1 Films on Different Organic Substrates Deposited by r.f. Sputtering

Transparent conducting ZnO:AI films with good adhesion, low resistivity and high transmittance have been prepared on polyptopylene adipate (PPA), polyisocyanate (PI) and polyester substrates by r.f. magnetron sputtering. The structural, electrical and optical properties of the obtained films were studied. The polycrystalline ZnO:AI films with resistivity as Iow as 5.76×10-4 Ω·cm,carrier concentration 9.06×1020 cm-a and Hall mobility 11.98 cm2 V-1s-1 were produced on PPA substrate by controlling the deposition parameters. The average transmittance of films on PPA is ～80% in the wavelength range of visible spectrum. The films on PPA substrates have better electrical and optical properties compared with the filmson other kinds of substrates.     

磁控溅射法制备的CdS:Al薄膜的性质研究

采用Al和CdS双靶共溅射的方法, 调控Al和CdS源的沉积速率, 制备出不同Al掺杂浓度的CdS:Al薄膜。通过XRD、SEM、AFM、紫外-可见透射光谱分析、常温霍尔测试对CdS: Al薄膜的结构、形貌、光学和电学性质进行表征。XRD结果表明, 不同Al掺杂浓度的CdS:Al薄膜均为六方纤锌矿结构的多晶薄膜, 并且在(002)方向择优生长。SEM和AFM结果表明, CdS:Al薄膜的表面均匀致密, 表面粗糙度随着Al掺杂浓度的增加略有增加。紫外-可见透射光谱分析表明, CdS:Al薄膜禁带宽度在2.42~2.46 eV 之间, 随着Al掺杂浓度的增加而略微减小。常温霍尔测试结果证明, 掺Al对CdS薄膜的电学性质影响显著, 掺Al原子浓度3.8%以上的CdS薄膜, 载流子浓度增加了3个数量级, 电阻率下降了3个数量级。掺Al后的CdS薄膜n型更强, 有利于与CdTe形成更强的内建场, 从而提高太阳电池效率。用溅射方法制备的CdS:Al薄膜的性质适合用作CdTe薄膜太阳电池的窗口层。     

等离子体源增强磁控溅射沉积Al2O3薄膜研究

采用电子回旋共振微波等离子体源增强磁控溅射沉积氧化铝薄膜.X射线光电子谱和X射线衍射分析表明,在600℃沉积温度下,Si（100）基片上获得了亚稳的具有化学计量配比成分、面心立方结构的γ-Al₂O₃薄膜.薄膜的折射率为1.7,与稳定的α-Al₂O₃体材料相当.     

ZnO:Al Films Prepared by Reactive Mid-frequency Magnetron Sputtering with Rotating Cathode

Al-doped zinc oxide (ZnO:Al,AZO) films were deposited on glass substrates using a reactive mid-frequency (MF) magnetron sputtering process with rotating cathodes.The influence of deposition parameters on structural,electrical and optical properties of AZO films is investigated.It is observed that the rotating magnetron targets exhibited a sputtered metallic surface over a wider range,and there is no re-deposition zone between the racetracks.The films deposited at static deposition mode demonstrate more homo...     

Substrate Temperature Dependent Properties of Cu Doped NiO Films Deposited by DC Reactive Magnetron Sputtering

The NiO—Cu composite films were deposited on a glass substrate at various substrate temperatures by DC reactive magnetron sputtering technique.The effect of substrate temperature on the structural,optical, morphological and electrical properties of the films was mainly investigated.X-ray diffraction studies revealed that when the substrate temperature increased to above 200℃,the preferred orientation tended to move to another preferred site from(220) to(111) and had a stable cubic structure.The optical transmittance and band gap values increased with increasing substrate temperature.From the morphological studies,it was observed that the grain size and root mean square roughness were increased with increasing substrate temperature.The electrical resistivity of the film decreased to 0.017Ωcm at high substrate temperature of 400℃.     

直流磁控溅射法制备ZnO：Zr透明导电薄膜及性能研究

利用直流磁控溅射法在玻璃衬底上制备了ZnO光电性能的影响.研究结果表明,厚度对薄膜的结构和电学性能有很大的影响.制备的ZZO薄膜为六角纤锌矿结构的多晶薄膜,具有C轴择优取向.在厚度为593nm时,薄膜的电阻率具有最小值1.9×10-3Ω·cm.所制备薄膜样品的可见光平均透过率都超过93%.     

Ar Pressure Dependence of the Properties of Molybdenum-doped ZnO Films Grown by RF Magnetron Sputtering

Transparent conducting oxide film of molybdenum-doped zinc oxide （MZO） with high transparency and relatively low resistivity was prepared by RF （radio frequency） magnetron sputtering at room temperature. The structural, electrical, and optical properties of the films deposited under different Ar pressure were investigated.XRD （X-ray diffraction） patterns show that the nature of the films is polycrystalline with a hexagonal structure and a preferred orientation along the c-axis. The resistivity increases as Ar pressure increases. The lowest range exceeds 88% for all the samples. The optical band gap decreases from 3.27 to 3.15 eV with increasing Ar pressure from 0.6 to 3.0 Pa.