溶液法制备的氧化锌多层膜及其场效应性质(英文)

通过旋涂法,采用不同浓度的前躯体制备了氧化锌多层膜,并制备了基于此多层膜的薄膜晶体管器件.实验证明,基于按照氧化锌前躯体浓度顺序为0.25、0.10和0.05 mol.L-1依次旋涂前躯体溶液制备的氧化锌薄膜的晶体管器件的载流子迁移率为0.02 cm.2V-.1s-1,高于按照浓度顺序为0.05、0.10和0.25 mol.L-1依次旋涂前躯体溶液制备的氧化锌薄膜的载流子迁移率(0.013 cm2.V-.1s-1).原子力显微镜(AFM)结果表明,前一种薄膜粗糙度的均方根值(rms)为3.95 nm,而后一种薄膜粗糙度的rms远远高于前者,为4.52 nm,这就说明了氧化锌薄膜的粗糙度对薄膜的半导体性质有很大的影响,这是由于平整的薄膜有利于形成理想的源/漏电极与半导体层的接触.在晶体管中,起传输作用的半导体层是靠近ZnO/SiO2界面处的几纳米的半导体层中的氧化锌晶粒,因此起始形成的氧化锌薄膜的结晶度影响着晶体管的性能.采用X射线衍射(XRD)测试了多层膜中起始形成的薄膜的结晶性能.对于前一种薄膜,起始形成的薄膜为多晶薄膜,而对于后一种薄膜,起始形成的薄膜是无定形薄膜.因此,粗糙度以及起始形成的薄膜的结晶度影响着多层半导体薄膜的性质.     

吲哚方酸菁半导体在场效应晶体管中的应用

研究了2,3,3-三甲基-1-H-吲哚方酸菁的场效应性质, 通过X射线衍射证实了方酸菁分子内电荷分离结构以及分子间面面堆积模式, 并在Si/SiO₂基片上通过真空蒸镀和旋涂的方法制备了p型晶体管器件. 通过对器件性能与沟道形态的研究, 我们发现退火处理能促进方酸菁薄膜由无定形态向多晶态转变, 从而使薄膜晶体管的迁移率从10^-5 cm²?V^-1?s^-1量级提高到10^-3 cm²?V^-1?s^-1量级. 顶接触结构单晶器件获得了7.8×10^-2 cm²?V^-1?s^-1的迁移率. 未封装的方酸菁晶体管在大气中也表现出较好的稳定性.     

磁控溅射中靶-基底距离与Si共掺对ZnO:Al薄膜性质的影响

使用射频磁控溅射, 在正方形石英衬底上沉积透明导电掺Al的ZnO(AZO)和Si共掺AZO(AZO:Si)薄膜. 系统研究了靶-基底距离(D_st)和Si共掺对AZO薄膜电学、光学性质的影响. 电阻率、载流子浓度和迁移率都强烈地依赖于靶-基底距离, 随着靶-基底距离的减少, 载流子浓度和迁移率都有显著的增加, 电导率也随之提高. 在靶-基底距离为4.5 cm处, 得到最低电阻率4.94×10^-4 Ω·cm, 此时的载流子浓度和迁移率分别是3.75×10²⁰ cm^-3和33.7 cm²·V^-1·s^-1. X射线光电子能谱(XPS)、X射线衍射(XRD)和边界散射模型被用于分析载流子浓度、迁移率和靶-基底距离的关系. 透射谱显示, 在可见-近红外范围内所有样品均有大于93%的平均透射率, 同时随着靶基距离的减少, 吸收边蓝移. AZO:Si表现出可与AZO相比拟的高电导和高透射光学特性, 但在热湿环境中却有着更好的电阻稳定性, 这在实际使用中很有意义.     

高结晶度方酸菁染料全溶液制备平面异质结有机太阳能电池

高结晶度有机半导体材料由于分子紧密堆叠,电荷迁移率高,但其在普通有机溶剂中溶解度低,溶液可加工性较差,限制了其在有机光电产品中的应用。本文设计合成了一种甲基修饰的高结晶度方酸菁类染料(DM-SQ),利用三氟乙酸溶剂溶液涂布制备DM-SQ薄膜。研究发现溶液制备的DM-SQ薄膜结晶度高,与真空沉积的DM-SQ薄膜比较,空穴迁移率更高(5.28×10_^-4 vs. 7.53×10_^-5 cm_² v_^-1 s_^-1)。以DM-SQ作为给体,PC₆₁BM作为受体,制备了平面异质结太阳能电池。溶液法制备的器件平均能量转换效率明显高于真空沉积器件(6.08±0.19％和3.56±0.22％)。     

尖晶石Li4Ti5O12中锂离子的化学扩散系数的研究

A relatively simple galvanostatic method was used for the evaluation on the average chemical diffusion coefficient of lithium-ion in spinel Li₄Ti₅O₁₂ prepared by solid-state reaction technique. The diffusion coefficient of lithium-ion was estimated to be 2.8×10^-13 cm²·s^-1 and 1.3×10^-13 cm²·s^-1 for charge and discharge， respectively.     

辐照三嵌段聚苯乙烯-丁二烯-4-乙烯基吡啶共聚物离子交换膜性能的研究——Ⅱ.共聚物膜的基本性能及分离实验

 本文研究了以辐照聚苯乙烯-丁二烯-4-乙烯基吡啶嵌段共聚物为膜基体所制成的嵌镶离子交换膜的基本性能.研究表明所制备的嵌镶膜在两端浓度分别为0.1及0.001 mol/L KCl 中的水渗析系数及电解质渗析系数分别是2.40×10^-5mol/cm²·min及2.10×10^-8mol/cm²·s.用所制备的嵌镶离子交换膜测试了牛血清白蛋白(M=67,000)与KCl混合溶液,蔗糖(M=343)与KCl混合溶液的膜分离效果.实验表明对上述两种非电解质均不能通过膜、而电解质KCl则可以.上述两种混合溶液中KCl渗透系数分别为J_KCl(牛血清白蛋白)=1.08×10^-8mol/cm²·s及J_(KCl)(蔗糖)=1.10×10^-8mol/cm²·s.     

Diffusion of Noble Metals,Zn and Ge in GaSb Single Crystals

Diffusion of Cu, Ag, Au, Ge and Zn in single crystal gallium antimonide has been carried out by measuring Hall effect according to van der Pauw, conductivity, energy dispersive X-ray (EDX) and surface electron microscopy. The best results have been obtained in excess of antimony. The resulting diffusion data in GaSb are diffusivity D_o, activation enthalpy Q, carrier density p and mobility μ at 300 K: Ag: D_o=1.8·10⁻⁴ cm² s⁻¹, Q=1.2 eV, p=6·10¹⁸ cm⁻³, μ=550 cm² (Vs)⁻¹ Au: D_o=6.6·10⁺³ cm² s⁻¹, Q=2.7 eV, p=5·10¹⁸ cm⁻³, μ=500 cm² (Vs)⁻¹ Cu: D_o=3.2·10⁺⁸ cm² s⁻¹, Q=2.7 eV, p=2·10¹⁸ cm⁻³, μ=150 cm² (Vs)⁻¹ Zn: D_o=9.2·10⁻² cm² s⁻¹, Q=1.8 eV, p=2·10²⁰ cm⁻³, μ=80 cm² (Vs)⁻¹ Ge: D_o=1.0·10⁻¹ cm² s⁻¹, Q=1.7 eV, p=1·10¹⁹ cm⁻³, μ=320 cm² (Vs)⁻¹. This revised version was published online in August 2006 with corrections to the Cover Date.     

多元杂环萘二酰亚胺衍生物的合成及其场效应性能研究

杂环修饰的萘二酰亚胺(NDI)类化合物由于其独特的光电性能被研究人员广泛关注,并应用于有机场效应晶体管(OFETs)、有机太阳能电池中(OSCs)、传感器等领域。但是含有给受体单元的多元杂环萘二酰亚胺衍生物的合成并不容易,本文通过简单高效的方法设计合成了含有氮、硫原子的11个杂环类萘二酰亚胺衍生物,并通过紫外可见吸收光谱、循环伏安曲线和X射线衍射对其进行了物性研究。通过溶液旋涂法,制备了该材料的底栅底接触场效应晶体管器件,在空气中表现出p型半导体性能,当退火温度为140 ℃时性能达到最优,其空穴迁移率为0.2 cm_²?V_^-1?s_^-1。     

超级电容器用无定形V2O5电容性能研究

本文采用淬冷法制备了V₂O₅样品。采用FTIR、XRD对其进行了表征。结果表明所制样品为无定形V₂O₅。通过循环伏安法和恒电流充放电测试研究其电容特性，并探讨了电化学反应机理。电化学性能测试结果表明，水基电解液种类及浓度、电压范围、扫描速度、电流密度均对无定形V₂O₅ 电容性能产生影响。在1 mol·L^-1 NaNO₃溶液中，电位窗口为-0.2～0.8 V(vs SCE)范围内，5 mV·s^-1的扫描速度下，无定形V₂O₅具有良好的电容性能；在250 mA·g^-1的电流密度下，比电容为185.1 F·g^-1，循环性能良好。     

二维过渡金属硫族化合物缺陷工程

二维过渡金属硫族化合物（two-dimensional transition metal dichalcogenides,TMDs）具有厚度在原子级别、禁带宽度随层数在1~2 eV内变化、高载流子迁移率（如MoS₂载流子迁移率达到了200 cm²·V^-1·s^-1）等特点,在光学、电学等领域具有广泛应用。TMDs的超薄特性使此类材料与块体材料相比,更容易受到缺陷调控的影响,改变材料原有性能。在本综述中,首先介绍了TMDs的晶体结构和相结构,并根据维度特征对缺陷的类型进行了分类;接着从缺陷的抑制和修复,以及缺陷的制造两方面出发,总结了缺陷调控TMDs材料性能的最新研究进展;在此基础上,介绍了缺陷工程在电学、光学、磁学、电催化等领域的具体应用;最后,本综述讨论了缺陷工程在应用过程中面临的实际问题,并对其未来的研究及发展方向进行了展望。     

Effect of acetic acid on the performance of solution-processed gallium doped indium oxide thin film transistors

We investigated a role of acetic acid for solution processed gallium doped indium oxide thin film transistors (TFTs). By adding acetic acid in solution instead of commonly used ethanolamine, electrical performance of GIO TFTs is significantly enhanced. We demonstrated that acetic acid plays a role in enhancing crystallinity, lowering decomposition temperature and reducing hydroxyl groups in the film. The GIO TFTs formed from acetic acid added solution have mobility of 12.68 cm² V^?1 s^?1, threshold voltage of ?7.4 V, on/off current ratio of 1.07 × 10⁸ and subthreshold slope of 0.78 V/decade.     

Yttrium Doped Copper (II) Oxide Hole Transport Material as Efficient Thin Film Transistor

This work reports development of yttrium doped copper oxide (Y−CuO) as a new hole transport material with supplemented optoelectronic character. The pure and Y-doped CuO thin films are developed through a solid-state method at 200 °C and recognized as high performance p-channel inorganic thin-film transistors (TFTs). CuO is formed by oxidative decomposition of copper acetylacetonate, yielding 100 nm thick and conductive (40.9 S cm⁻¹) compact films with a band gap of 2.47 eV and charge carrier density of ∼1.44×10¹⁹ cm⁻³. Yttrium doping generates denser films, Cu₂Y₂O₅ phase in the lattice, with a wide band gap of 2.63 eV. The electrical conductivity increases nine-fold on 2 % Y addition to CuO, and the carrier density increases to 2.97×10²¹ cm⁻³, the highest reported so far. The TFT devices perform remarkably with high field-effect mobility (μ_sat) of 3.45 cm² V⁻¹ s⁻¹ and 5.3 cm² V⁻¹ s⁻¹, and considerably high current-on/off ratios of 0.11×10⁴ and 9.21×10⁴, for CuO and Y−CuO films, respectively (at −1 V operating voltage). A very small width hysteresis, 0.01 V for CuO and 1.92 V for 1 % Y−CuO, depict good bias stability. Both the devices work in enhancement mode with stable output characteristics for multiple forward sweeps (5 to −60 V) at −1V_g.     

聚吡咯薄膜的电特性

含有不同的链长的w-吡咯烷基二甲基氯硅烷作为粘合剂通过自组装（SAMs）吸附于二氧化硅表面,然后聚吡咯膜化学沉积于该粘合剂修饰的表面。化学沉积的聚吡咯膜的表面形貌用扫描电镜（SEM）及原子力显微镜（AFM）表征。除短链外不同链长的粘合剂对聚吡咯膜的厚度影响不大。聚吡咯膜的电特性用电流-电压表征。结果显示电流与粘合剂的链长无关。电特性表明载流子迁移率为1.4 ´ 10-4 cm2×V-1.s –1。     

Electrochemical Responses and Sensitivities of Films Based on Multi-Walled Carbon Nanotubes in Aqueous Solutions

Novel films consisting of multi-walled carbon nanotubes (MWCNTs) were fabricated by means of chemical vapor deposition with decomposition of either acetonitrile (ACN) or benzene (BZ) using ferrocene as catalyst. The electrochemical responses of MWCNT-based films towards the ferrocyanide/ferricyanide, [Fe(CN)₆]^3?/4? redox couple were probed by means of cyclic voltammetry and electrochemical impedance spectroscopy at 25.0?±?0.5?°C. Both MWCNT-based films exhibit Nernstian response towards [Fe(CN)₆]^3?/4? with some slight kinetic differences. Namely, heterogeneous electron transfer rate constants lying in ranges of 2.69?×?10^?2?C1.7?×?10^?3 and 9.0?×?10^?3?C2.6?×?10^?3?cm·s^?1 were obtained at v?=?0.05?V·s^?1 for MWCNT_ACN and MWCNT_BZ, respectively. The detection limit of MWCNT_ACN, estimated to be about 4.70?×?10^?7?mol·L^?1 at v?=?0.05?V·s^?1, tends to become slightly poorer with the increase of the scan rate, namely at v?=?0.10?V·s^?1 the detection limit of 1.70?×?10^?6?mol·L^?1 was determined. Slightly poorer response ability was exhibited by MWCNT_BZ; specifically the detection limits of 1.57?×?10^?6 and 4.35?×?10^?6?mol·L^?1 were determined at v?=?0.05 and v?=?0.10?V·s^?1, respectively. The sensitivities of MWCNT_ACN and MWCNT_BZ towards [Fe(CN)₆]^3?/4? were determined as 1.60?×?10^?7 and 1.51?×?10^?7?A·L·mol^?1·cm^?2, respectively. The excellent electrochemical performance of MWCNT_ACN is attributed to the presence of incorporated nitrogen in the nanotube??s structure.     

Transparent amorphous Indium-Gallium-Zinc-Oxygen thin film transistors using solution technology at low temperature

Transparent amorphous Indium-Gallium-Zinc-oxide thin films transistors (a-IGZO TFTs) were fabricated using spin-coating technique at a relative low annealing temperature of 300 °C. The effects of the gallium (Ga) concentration on the properties of the IGZO solutions, the optical properties of the a-IGZO films,and the a-IGZO TFTs device properties were researched. The a-IGZO thin films were uniform and smooth, root mean square roughness of IGZO films was less than 0.4 nm, and the transmittance was more than 80 % in the visible wavelength. The results showed that An appropriate amount of Ga doping and annealing temperature could significant improve the a-IGZO TFTs’ device performance. A saturation mobility of 0.04 cm² V^?1 s^?1 was obtained when the Ga concentration reached 10.7 %.     

Sol–gel processed indium zinc oxide thin film and transparent thin-film transistors

Indium–zinc oxide (IZO) thin films were fabricated by spin coating using acetate- and nitrate-based precursors, and thin film transistors (TFTs) were further fabricated employing the IZO films as the active channel layer. The impact of the indium concentration on the properties of the solutions, the structure and optical transmittance properties of the IZO films and the IZO TFTs device properties were researched in this article. The IZO films with amorphous structure were obtained when the annealing temperature is 500 °C. The transmittance could reach ~90 % (including glass substrate) during the visible region of 400–760 nm. Higher indium concentration can improve the IZO TFTs’ filed effect mobility. A I_on–I_off of 6.0 × 10⁶ and a mobility of 0.13 cm²/Vs were obtained when the indium concentration is 60 %. IZO TFTs’ performance could deteriorate when the indium concentration more than 60 %.     

Highly transparent solution processed In-Ga-Zn oxide thin films and thin film transistors

Highly transparent In-Ga-Zn oxide (IGZO) thin films were fabricated by spin coating using acetate- and chlorate-based precursors, and thin film transistors (TFTs) were further fabricated employing these IGZO films as the active channel layer. The impact of the post-annealing temperature on the physical properties of IGZO films and performance of IGZO TFTs were investigated. Compared to the nitrate-based IGZO precursor, the chlorate-based precursor increases the phase change temperature of IGZO thin films. The IGZO films changed from amorphous to nanocrystalline phase in an annealing temperature range of 600–700 °C. The transparency is more than 90% in the visible region for IGZO films annealed with temperatures higher than 600 °C. With the increase of post-annealing temperature, the carrier concentration of IGZO film decreases, while the sheet resistance increases firstly and then saturates. The bottom-gate TFT with IGZO channel annealed at 600 °C in oxygen showed the best performance, which was operated in n-type enhancement mode with a field effect mobility of 1.30 cm²/V s, a threshold voltage of 10 V, and a drain current on/off ratio of 2.5 × 10⁴.     

A High‐Performance Organic Field‐Effect Transistor Based on Platinum(II) Porphyrin: Peripheral Substituents on Porphyrin Ligand Significantly Affect Film Structure and Charge Mobility

Organic field‐effect transistors incorporating planar π‐conjugated metal‐free macrocycles and their metal derivatives are fabricated by vacuum deposition. The crystal structures of [H₂(OX)] (H₂OX=etioporphyrin‐I), [Cu(OX)], [Pt(OX)], and [Pt(TBP)] (H₂TBP=tetra‐(n‐butyl)porphyrin) as determined by single crystal X‐ray diffraction (XRD), reveal the absence of occluded solvent molecules. The field‐effect transistors (FETs) made from thin films of all these metal‐free macrocycles and their metal derivatives show a p‐type semiconductor behavior with a charge mobility (μ) ranging from 10^?6 to 10^?1 cm² V^?1 s^?1. Annealing the as‐deposited Pt(OX) film leads to the formation of a polycrystalline film that exhibits excellent overall charge transport properties with a charge mobility of up to 3.2×10^?1 cm² V^?1 s^?1, which is the best value reported for a metalloporphyrin. Compared with their metal derivatives, the field‐effect transistors made from thin films of metal‐free macrocycles (except tetra‐(n‐propyl)porphycene) have significantly lower μ values (3.0×10^?6–3.7×10^?5 cm² V^?1 s^?1).     

基于多壁碳纳米管和氧化锌纳米棒复合物的葡萄糖生物传感器(英文)

利用多壁碳纳米管(MWCNTs)和氧化锌(ZnO)纳米棒复合物膜构建了一种新的电流型葡萄糖生物传感器。MWCNTs-ZnO复合物在超声协助下通过静电配位的方式产生。其中,ZnO纳米棒的存在加强了该复合物催化氧化H2O2的能力,增加了响应电流。与单一的MWCNTs和ZnO相比,这种纳米复合物显示了更为有效地电催化活性。在此基础上,我们以MWCNTs-ZnO复合物膜为基底,用戊二醛交联法固定葡萄糖氧化酶,电聚合邻苯二胺(PoPD)膜为抗干扰层,构建了抗干扰能力强,稳定性好,灵敏度高,响应快的葡萄糖传感器。在+0.8V的检测电位下,该传感器对葡萄糖响应的线性范围为5.0×10-6~5.0×10-3mol·L-1(R=0.997),检测限为3.5×10-6mol·L-1(S/N=3),响应时间小于10s的葡萄糖生物传感器,常见干扰物质如抗坏血酸和尿酸不影响测定。