磁控溅射法制备复合绝缘层的薄膜晶体管

研究了磁控溅射法制备的复合绝缘层结构的有机薄膜晶体管.该器件是以酞菁铜(CuPc)作为有源层,SiO2/Si3N4/SiO2复合绝缘层和单层SiO2为绝缘层来进行对比研究的.结果显示与单层SiO2绝缘层的器件相比,具有复合绝缘层的器件结构能有效改进有机薄膜晶体管的性能.同时发现,不同厚度的SiO2/Si3N4/SiO2复合绝缘层对晶体管的性能也有影响,绝缘层太厚,感应电流小;绝缘层太薄,器件容易被击穿.     

氧分压对磁控溅射制备IGZO薄膜光电特性的影响

通过磁控溅射技术在玻璃基板上制备氧化铟镓锌(IGZO)薄膜,为了研究不同氧分压对IGZO薄膜结构及光电特性的影响,在不同的氧分压0,0.015,0.06和0.24 Pa下制备了不同样品。样品的沉积速率、成分结构、面电阻及光电性质分别用椭偏仪、X射线光电子能谱(XPS)和四点探针等方法进行了测量。实验结果表明,随着氧分压的增大,IGZO薄膜的沉积速率呈下降趋势,不同氧分压的IGZO薄膜的元素比例(In∶Ga∶Zn)差异不大,在可见光的范围内其氧分压为0 Pa以上时,IGZO薄膜平均透过率均超过80%,阻值随氧分压的增加而增大。制作了不同氧分压以IGZO为沟道层的薄膜晶体管,其迁移率为5.93~9.42 cm2·V-1·s-1,阈值电压为3.8~9.2 V。     

ZnO薄膜的射频磁控溅射制备及性能研究

采用射频磁控溅射法在玻璃衬底上制备出高质量的ZnO薄膜.对薄膜的结构和性能进行了研究.所制备的ZnO是具有六角纤锌矿结构的多晶薄膜,最佳择优取向为(002)方向.ZnO薄膜的霍尔迁移率和载流子浓度分别为8×104m2/(V·s)和11.3×1020 cm-3.     

RF磁控溅射法原位制备C轴择优取向ZnO薄膜

采用RF磁控溅射法在玻璃衬底上原位低温生长ZnO薄膜.生长出的薄膜对可见光具有高于90%的透射率,该薄膜具有良好的C轴取向.利用X射线衍射(XRD)的测试结果,分析了溅射工艺条件如衬底温度、氩氧比和溅射气压等对薄膜性能的影响,得到最佳的生长工艺条件为:衬底温度300 ℃,溅射气压1 Pa,氩氧比为25 sccm∶15 sccm.在此条件下生长的ZnO薄膜具有良好的C轴择优取向,并且薄膜的结晶性能良好.采用这种方法制备的ZnO薄膜适合用于制备平板显示器的透明薄膜晶体管和太阳电池的透明导电电极.     

磁控溅射和热氧化法制备ZnO纳米颗粒

利用射频磁控共溅射技术在Si(111)衬底上沉积金属锌／二氧化硅基质(Zn/SiO2)复合薄膜。在空气中600℃退火60min，从SiO2基质中析出的金属Zn被空气中O2氧化生成了ZnO纳米颗粒，并形成了SiO2多孔网络结构。用X射线衍射(XRD)、扫描电子显微镜(SEM)和光致发光谱(PL)对样品的组成、结构、表面形貌及发光特性进行了分析。结果表明，生成的ZnO纳米颗粒为六角纤锌矿结构，呈近椭圆形，平均尺寸在65nm左右。在280nm光激发下，有较强的370nm近带边激子跃迁紫外光发射和峰位在460nm处较弱的蓝色发光。     

射频磁控溅射制备声表面波器件用ZnO薄膜

研究了采用射频磁控溅射法在SiO2/Si衬底上制备ZnO薄膜工艺中溅射功率、氧氩比(V(O2)/V(Ar))及衬底温度对ZnO薄膜结构的影响。利用X-射线衍射(XRD)和扫描力显微镜(AFM)对薄膜进行结构性能分析,表明其结构性能随工艺参数变化的规律。利用优化的工艺条件:射频功率60 W、V(O2)/V(Ar)为0.55和衬底温度350℃,在DLC/Si衬底上制备了ZnO薄膜,制作加工成声表面波滤波器件,测试分析了频率响应特性,中心频率为596.5 MHz。     

中频脉冲磁控溅射制备ZnO:Al透明导电薄膜

采用中频磁控溅射工艺,以2%的Al掺杂的Zn(纯度99.99%)金属材料为靶材制备平面及绒面透明导电ZnO:Al(ZAO)薄膜,系统研究了衬底温度、工作气压和溅射功率等对平面ZAO结构和光电特性的影响,并对湿法腐蚀制备绒面ZAO薄膜进行了介绍。获得了适合太阳电池的高性能薄膜,其电阻率为4.6×10-4Ω·cm,载流子浓度为4.9×1020cm-3,霍尔迁移率为56cm2/V·s,可见光范围内(400~800nm)的平均透过率大于85%。     

氧含量对RF磁控溅射ZnO薄膜结构特性的影响

采用射频(RF)磁控溅射的方法,通过改变工作气氛中氩气和氧气的比例,在Si(100)衬底上沉积出具有高度C轴择优取向的ZnO薄膜.实验发现随着O2/(Ar O2)比的增加,薄膜的沉积速率下降.O2/(Ar O2)比对薄膜结晶状态有明显影响,O2/(Ar O2)比约为0.45,薄膜结晶质量较好.     

氧化锌薄膜生长与ZnO基薄膜晶体管制备

通过金属有机化学气相沉积(MOCVD)方法生长ZnO薄膜.XRD测试显示出(002)晶面的强衍射峰,表明生长的ZnO 薄膜是主度的c轴取向.基于 ZnO 薄膜基础,我们制备了 ZnO 基薄膜晶体管.     

Nb/Nd共掺Bi4Ti3O12对ZnO基薄膜晶体管性能的影响

利用化学溶液沉积(CSD)法,在Pt/Ti/SiO2/Si(100)衬底上成功制备以B3.15Nd0.85Ti3-x NbxO12(BNTNx,x=0.01,0.03,0.05,0.07)薄膜作为栅介质层、以ZnO薄膜作为有源层的铁电薄膜晶体管(ZnO/BNTN铁电TFT)。研究了Nb含量对BNTN薄膜微结构、介电和铁电性能的影响。结果表明,BNTN0.03薄膜的剩余极化(2 Pr)最大(71.4μC/cm2),介电常数最大(370)。测得BNTNx薄膜的居里温度约为410℃,介电损耗(tanδ)约为0.02。ZnO/BNTN铁电TFT相比ZnO/SiO2层TFT,有较好的输出特性和转移特性,其阈值电压、沟道迁移率、存储窗口和开关电流比分别达到了2.5V、5.68cm2/Vs、1.5V和1.8×105。     

RF磁控溅射技术制备纳米硅

利用硅-SiO2复合靶,RF磁控溅射技术制备了三种富硅量不同的SiO2薄膜,并在较大的温度范围内进行了退火。利用x射线光电子能谱,对刚淀积的样品进行了分析,结果表明三种样品都存在纳米硅粒子。使用高分辨率透射电子显微镜和电子衍射技术研究了退火后样品中纳米硅粒子析出和结晶情况,富硅量较大的两种SiO2薄膜都观测到纳米硅晶粒。统计结果表明:复合靶中硅组分从20%增加到30%,纳米硅晶粒的平均尺寸增加了15%、密度增加了2.5倍,而且随着退火温度从900℃增加到1100℃,纳米硅晶粒的平均尺寸和密度都明显增加。     

磁控溅射制作金红石——TiO_2

用磁控溅射方法制备了粒径大小为20nm的金红石———TiO2,用X射线(XRD)和扫描电镜(SEM)观察表面形貌,局部表观致密,颗粒大小均匀。     

直流磁控溅射法制备ZnO:W透明导电薄膜及其性能表征

利用直流磁控溅射法成功地在室温玻璃衬底上制备出了电阻率低、透光率高的掺钨氧化锌（ZnO:W）透明导电薄膜。沉积压强在12-21 Pa之间变化。X射线衍射结果表明实验制备的ZnO:W为六方纤锌矿结构的多晶薄膜,具有垂直于衬底方向的c轴择优取向。沉积压强对ZnO:W薄膜的晶化程度、形貌和电阻率有很大影响,而对其透光率和光学带隙及折射率影响不大。当沉积压强为21 Pa,溅射功率为130 W时,所制备薄膜的电阻率达到最小值1.5×10-4 Ω·cm,其方块电阻、可见光透过率分别为6.8 Ω/□和91.3%。     

Preparation and characterization of transparent conducting ZnO:W films by DC magnetron sputtering

Tungsten-doped zinc oxide（ZnO:W） films with low resistivity and high transmittance were successfully deposited on glass substrates by direct current magnetron sputtering at low temperature.The deposition pressure is varied from 12 to 21 Pa.The X-ray diffraction results show that all of the deposited films are polycrystalline and have a hexagonal structure with a preferred c-axis orientation.The crystallinity,morphologies and resistivity of ZnO:W films greatly depend on deposition pressure while the optical properties including optical transmittance, optical band gap as well as refractive index are not sensitive to deposition pressure.The deposited films with an electrical resistivity as low as 1.5×10^-4Ω·cm,sheet resistance of 6.8Ω/□and an average transmittance of 91.3% in the visible range were obtained at a deposition pressure of 21 Pa and sputtering power of 130 W.     

Facile polymer gate dielectric surface-modification for organic thin-film transistors using self-assembled surfactant layer

We demonstrate facile polymer gate dielectric surface-modification method for organic thin-film transistors (OTFTs). We simply introduce self-assembled surfactant layer onto the top surface of poly(4-vinylphenol) (PVP) dielectric by spin coating PVP solution mixed with sodium dodecyl sulfate and tridecafluorohexane-1-sulfonic acid potassium salt as additive agents. The surfactant-modified PVP layer acquires various merits compared to pristine PVP layer in terms of surface smoothness and hydrophobicity, as confirmed by contact angle measurement, atomic force microscopy analyses, grazing incident X-ray diffraction and near-edge X-ray absorption fine structure spectroscopy. The resulting OTFTs with the conventional semiconducting poly(2,5-bis(3-hexadecylthiophen-2-yl)thieno[3,2-b]thiophene) as the active layer and surfactant-modified PVP as the dielectric layer reveal overall ascendency over the OTFT with pristine PVP, especially in terms of operating hysteresis and reliability. The effects of hydrophobicity of surfactants on the surface properties of PVP as well as the OTFT performances are fully discussed in conjunction with various characterization tools.     

Epitaxial growth of ZnO on GaN/sapphire substrate by radio-frequency magnetron sputtering

Zinc oxide (ZnO) thin films were grown on n-GaN/sapphire substrates by radio-frequency (RF) magnetron sputtering. The films were grown at substrate temperatures ranging from 400 to 700 ℃ for 1 h at a RF power of 80 W in pure Ar gas ambient. The effect of the substrate temperature on the structural and optical properties of these films was investigated by X-ray diffraction (XRD), atomic force microscopy (AFM) and photoluminescence (PL) spectra. XRD results indicated that ZnO films exhibited wurtzite symmetry and c-axis orientation when grown epitaxially on n-GaN/sapphire. The best crystalline quality of the ZnO film is obtained at a growth temperature of 600 ℃. AFM results indicate that the growth mode and degree of epitaxy strongly depend on the substrate temperature. In PL measurement, the intensity of ultraviolet emission increased initially with the rise of the substrate temperature, and then decreased with the temperature. The highest UV intensity is obtained for the film grown at 600 ℃ with best crystallization.     

利用磁控溅射在GaN/蓝宝石衬底上生长ZnO薄膜

Zinc oxide (ZnO) thin films were grown on n-GaN/sapphire substrates by radio-frequency (RF) magnetron sputtering. The films were grown at substrate temperatures ranging from 400 to 700 ℃ for 1 h at a RF power of 80 W in pure Ar gas ambient. The effect of the substrate temperature on the structural and optical properties of these films was investigated by X-ray diffraction (XRD), atomic force microscopy (AFM) and photoluminescence (PL) spectra. XRD results indicated that ZnO films exhibited wurtzite symmetry and c-axis orientation when grown epitaxially on n-GaN/sapphire. The best crystalline quality of the ZnO film is obtained at a growth temperature of 600 ℃. AFM results indicate that the growth mode and degree of epitaxy strongly depend on the substrate temperature. In PL measurement, the intensity of ultraviolet emission increased initially with the rise of the substrate temperature, and then decreased with the temperature. The highest UV intensity is obtained for the film grown at 600 ℃ with best crystallization. oindent     

透明导电薄膜ZnO:Zr的反应磁控溅射法制备及表征

以Zn金属靶和Zr金属片组成的Zn:Zr为靶材,利用直流反应磁控溅射法在玻璃衬底上制备ZnO:Zr透明导电薄膜。研究了靶与衬底之间的距离对所制备薄膜结构和性能的影响。实验制备的ZnO:Zr薄膜为六方纤锌矿结构的多晶薄膜,且具有与衬底方向垂直的c轴择优取向。实验结果表明,靶与衬底之间的距离对ZnO:Zr薄膜的结构、生长速率、密度及电学性能有很大影响。靶与衬底之间的最佳距离为6.0cm,在此条件下制备的ZnO:Zr薄膜具有最小电阻率1.78×10-3Ω.cm,其可见光透过率为88.5%,折射率为2.04。     

Magnetic properties of ZnO:Cu thin films prepared by RF magnetron sputtering

ZnO films and ZnO:Cu diluted magnetic semiconductor films were prepared by radio frequency magnetron sputtering on Si (111) substrates, with targets of ZnO and Zn0.99Cu0.01 O, respectively. The plasma emission spectra were analyzed by using a grating monochromator during sputtering. The X-ray photoelectron spectroscopy measurements indicate the existence of Zni defect in the films, and the valence state of Cu is 1. The X-ray diffraction measurements indicate that the thin films have a hexagonal wurtzite structure and have a preferred orientation along the c-axis. The vibrating sample magnetometer measurements indicate that the sample is ferromagnetic at room temperature, and the origin of the magnetic behavior of the samples is discussed.     

磁控溅射NiO/ZnO透明异质结二极管及其光电特性研究

采用磁控溅射方法在ITO玻璃基板上沉积NiO,ZnO,AZO三层透明氧化物薄膜,成功制备了NiO/ZnO透明异质结二极管.实验结果表明,PN结展示出明显的I-V整流特性,正向开启电压1V;在氙灯光照条件下,二极管反向电流在5V偏置时,达到1.5 mA.二极管在可见光的平均透过率约为25%.