薄膜绝缘层对陶瓷厚膜电致发光显示器件的影响

采用丝网印刷技术，在Al2O3陶瓷板上印刷、高温烧结内电极及绝缘层制备出陶瓷厚膜基板，进而制备了新型厚膜电致发光显示器（TDEL），整个器件结构为陶瓷基板／内电极／厚膜绝缘层／发光层／薄膜绝缘层／ITO透明电极。对用不同薄膜绝缘材料制备的显示器件的特性进行测试、比较、分析，结果表明薄膜绝缘介质层对器件的阈值电压、发光亮度均有一定的影响，以复合绝缘层的性能最优。最后对器件的衰减特性进行了初步分析。     

以陶瓷厚膜为绝缘层的绿色薄膜电致发光器件

首次报道了采用高介电常数的陶瓷厚膜作绝缘层、ＺｎＳ∶Ｅｒ作发光层的绿色薄膜电致发光器件（ＣＴＦＥＬ）。器件结构为陶瓷基片／内电极／陶瓷厚膜／发光层（ＺｎＳ∶Ｅｒ）／透明电极（ＺｎＯ∶Ａｌ）。发光层是用电子束蒸发制备的,透明电极是采用溅射法制备的。器件在市电频率驱动下发出明亮的绿光,研究了器件的亮度－电压和效率－电压等特性。     

Ga2O3:Mn电致发光薄膜的微结构及光谱特性研究

采用电子束蒸发法在硅衬底或BaTiO3陶瓷基片上沉积了Ga2O3：Mn电致发光膜,并进行了不同温度热处理,制备了电致发光器件。用X射线衍射(XRD)分析了Ga2O3：Mn薄膜晶体结构;用荧光分光光度计测试了电致发光器件的发射光谱。研究了Ga：O。：Mn薄膜的晶体结构与其光谱特性之间的关系。实验结果表明,Ga2O3：Mn薄膜结晶度随热处理温度的提高而提高,且晶体结构和结晶取向也随之改变;经500℃热处理的Ga2O3：Mn薄膜电致发光器件发绿光,其光谱主峰分布在495～535nm之间,且随驱动电压增高,谱峰出现蓝移现象。     

Ga_2O_3∶Mn电致发光薄膜的微结构及光谱特性研究

采用电子束蒸发法在硅衬底或 Ba Ti O3陶瓷基片上沉积了 Ga2 O3∶Mn电致发光膜 ,并进行了不同温度热处理 ,制备了电致发光器件。用 X射线衍射 ( XRD)分析了 Ga2 O3∶ Mn薄膜晶体结构 ;用荧光分光光度计测试了电致发光器件的发射光谱。研究了 Ga2 O3∶ Mn薄膜的晶体结构与其光谱特性之间的关系。实验结果表明 ,Ga2 O3∶ Mn薄膜结晶度随热处理温度的提高而提高 ,且晶体结构和结晶取向也随之改变 ;经 5 0 0℃热处理的 Ga2 O3∶ Mn薄膜电致发光器件发绿光 ,其光谱主峰分布在 495～ 5 3 5 nm之间 ,且随驱动电压增高 ,谱峰出现蓝移现象     

以陶瓷厚膜为绝缘层的缘色薄膜电致发光器件

首次报道了采用高介电常数的陶瓷厚膜作绝缘层,ＺｎＳ：Ｅｒ作发光层的绿色薄膜电致发光器件。器件结构为陶瓷基片／内电极／陶瓷厚膜／发光层／透明电极。     

硅基PZT 热释电厚膜红外探测器的研制

在(100)单晶Si 衬底上,采用MEMS 工艺和丝网印刷方法制作了锆钛酸铅(PZT)厚膜热释电红外探测器,深入研究了PZT 厚膜材料的制备方法与器件加工工艺。采用四甲基氢氧化铵(TMAH)溶液腐蚀Si 衬底制备硅杯结构。为防止Pb 和Si 相互扩散,在Pt 底电极与SiO2/ Si 衬底之间通过射频反应溅射制备了Al2O3 薄膜阻挡层。采用丝网印刷在硅杯中制备了30 m 厚的PZT 材料,并用冷等静压技术提高厚膜的致密度,实现了PZT 厚膜在850℃的低温烧结。PZT 厚膜在1 kHz、25℃下的相对介电常数与损耗角正切分别为210 和0.017,动态法测得热释电系数为1.510-8Ccm-2K-1。最后制备了敏感元为3 mm3 mm 的单元红外探测器,使用由斩波器调制的黑体辐射,在调制频率为112.9 Hz 时测得器件的探测率达到最大值7.4107 cmHz1/2W-1。     

陶瓷厚膜介质电致发光器件特点和最新进展

总结了陶瓷厚膜介质电致发光器件(TDEL)的发展历程和近期进展.介绍和比较了TDEL器件的特殊结构和优异的显示特性,以及陶瓷厚膜介质的工艺特点及器件的成本.重点阐述了iFire技术公司的新颖的颜色转换彩色显示实现方案,并对其产业化前景作了展望.     

阴极耦合层对顶发射白光OLED器件光电性能的影响

为了分析不同阴极耦合层对顶发射白光OLED器件光电性能的影响,数值计算了半透明阴极组成的多层膜系(ETL/EIL/Mg:Ag/折射率匹配层)的透过率和损耗;同时,采用共阴极结构设计制备了顶发射白光OLED器件,并对不同折射率匹配层制备的顶发射白光OLED器件的光电特性进行了研究。结果表明:采用相同厚度LiF和Al2O3薄膜作为阴极耦合层时,多层膜系光学透过率和损耗曲线存在较大差异;在20mA/cm2电流密度下,随着观测角度的增大,采用LiF+Al2O3双层折射率匹配层制备的器件电致发光谱峰位发生蓝移,但在整个视角内,器件的色坐标均稳定在白光等能点附近,这表明顶发射白光器件的色坐标可以通过折射率匹配层调节,使得器件在较大视角范围均能实现白光发射。     

发光器件

阻挡层结构的蓝色有机发光二极管[中]/朱文清… //半导体光电.-2001,22(1).-45-472001100339陶瓷厚膜和薄膜混合电致发光器件[中]/朱文清…//半导体光电.-2001,22(2).-82-862001100340     

丝网印刷制备大面积多孔PZT热释电厚膜与器件

采用丝网印刷法在氧化铝基片上制备了大面积多孔PbZr0.3Ti0.7O3热释电厚膜与单元红外探测器。通过掺入Li2CO3与Bi2O3作为助烧剂,实现了厚膜在850℃下的低温烧结。通过保持合适的孔隙率,将厚膜的相对介电常数降低至原值的1/5以提高材料优值与探测率。厚膜在1 kHz、25℃下的相对介电常数与损耗角正切分别为94与0.017。测试了厚膜相对介电常数与损耗随温度的变化规律,测得其居里温度为425℃。通过动态法测试得到厚膜的热释电系数为0.9×10-8 Ccm-2K-1。使用由斩波器调制的黑体辐射,测得单元器件在8.5~2 217 Hz的电压响应与噪声,计算出器件的探测率为3.4×107~1.7×108cmHz1/2W-1。     

缓冲层对PMS-PNN-PZT压电厚膜材料性能的影响

采用丝网印刷的方法制备了PMS-PNN-PZT四元系压电厚膜陶瓷材料。研究了基板、下电极和PMS-PNN-PZT厚膜层三者之间的高温扩散作用,及SiO2缓冲层对PMS-PNN-PZT压电厚膜的压电性能以及显微结构的影响。用XRD和SEM分析材料的相组成、厚膜定位及压电层的显微结构。结果表明,缓冲层有效地阻止了三者之间的相互扩散,样品的d33、εr等都有所提高,所制得的压电厚膜d33为285pC/N,εr为1210,Qm为1330,kp为0.54。     

Integrating High-k Ceramic Thin Film Capacitors into Organic Substrates Via Low-Cost Solution Processing

Current organic package-compatible embedded decoupling capacitors are based on thick film (8-16 m) polymer-ceramic composites with dielectric constant (k) of 20-30 and do not have sufficient capacitance density to meet the impedance requirements for emerging high-speed circuits and high power density microprocessors. High-k/high capacitance density ceramics films that can meet the performance targets are generally deposited by high-temperature processing or costly vacuum technology (radio frequency sputtering, PECVD) which are expensive and also incompatible with organic packages. The objective of this project is to develop ultra thin films (100-300nm) with high dielectric constant using organic compatible processes to meet future decoupling applications. In the current study, direct deposition of crystalline ceramic films on organic boards at temperatures less than 100C was demonstrated with the hydrothermal method. Post-hydrothermal treatments were shown to minimize the defects in the as-synthesized hydrothermal barium titanate films and improve the breakdown voltage (BDV) and leakage characteristics. Thin films with high capacitance densities and breakdown voltages of 10V were demonstrated. As an alternate technique, sol-gel technology was also demonstrated to integrate ceramic thin films in organic packages. A major barrier to synthesis of sol-gel films on copper foils is the process incompatibility of the sol-gel barium titanate with the copper electrodes. To enable process compatibility, process variables like sol pyrolysis temperature and time, and sintering conditions/atmosphere were optimized. Capacitance densities above 1.1F/cm was demonstrated on commercial copper foils with a BDV above 10 V. The two technologies reported in this study can potentially meet midfrequency decoupling requirements of digital systems.     

A novel TFEL device using a high-dielectric-constant multilayer ceramic substrate

A novel composite-structure ac EL device using thin films and a ceramic substrate has been developed. A light-emitting thin film (ZnS:Mn) and ITO electrodes are deposited on a multilayer ceramic substrate consisting of a very high-dielectric ceramic insulating layer (εs∼ 10⁴), internal printed electrodes, and a ceramic base plate. This device features low operating voltage (40-80 V), breakdown-failure-free operation, and high legibility.     

有机场效应晶体管最新实验研究进展

介绍了近两年新报道的有机半导体材料,列举了其场效应性能参数;综述了有机场效应晶体管(OFET)在器件结构上的改进,重点阐述了基于常见有机功能层材料富勒烯及其衍生物、并五苯、聚3-己基噻吩的OFET对栅介质层及有机功能层与电极的界面的改进,讨论了器件结构改进对OFET阈值电压、开关比、载流子迁移率的影响;介绍了衬底温度、退火处理对OF-ET性能的影响。最后,针对有机场效应晶体管研究现状,指出未来研究中应注重开发高迁移率、高薄膜稳定性的有机功能材料和高介电常数、高成膜质量的有机栅介质材料,继续优化器件结构,改进制备工艺以提高器件性能。     

ALD氧化铝薄膜介电性能及其在硅电容器的应用

硅基高密度电容器是利用半导体3D深硅槽技术和应用高介电常数(高K)材料制作的电容。相比钽电容和多层陶瓷电容(MLCC),硅基电容具有十年以上的寿命、工作温度范围大、容值温度系数小以及损耗低等优点。文章研究原子层沉积(ALD)制备的Al2O3薄膜的介电特性,通过优化ALD原子沉积温度和退火工艺,发现在沉积温度420℃和O3气氛退火5 min下,ALD生长的Al2O3薄膜击穿强度可大于0.7 V/nm,相对介电常数达8.7。制成的硅基电容器电容密度达到50 nF/mm2,漏电流小于5 nA/mm2。     

High-pressure oxidation for thin gate insulator process

High-pressure oxidation of silicon was performed at a pressure of 8.9 kg/cm²at a temperature range of 650 to 950°C. The oxidation temperature dependence of the film density, refractive index, chemical etching rate, and residual stress was measured. The film density of the oxide film was found to increase with decreasing oxidation temperature. The refractive index of the film also increased with decreasing oxidation temperature. The residual stress was found to be dependent on the oxidation temperature. The dielectric breakdown strength of the oxide film was measured by the voltage ramping method. The defect density of the oxide film calculated from the distribution of dielectric breakdown strength slightly decreased with decreasing oxidation temperature. The surface-state density of the oxide film was about 1.1 × 10¹¹cm^-2throughout the oxidation temperature range. The oxide grown on a doped polysilicon layer at a temperature of 750°C was five times as thick as the oxide simultaneously grown on the silicon substrate. The high-pressure and low-temperature oxidation was applied to the fabrication process of a device with a double polysilicon layer structure.     

片式陶瓷电容器技术的新进展

电子设备表面安装技术（ＳＭＴ）和小型化的进展，促使电子元件包括陶瓷电容器的片式化率不断提高，尺寸不断缩小。提高瓷料的介电常数，减小介质层的厚度，保持电极可靠的接触及降低瓷料的焙烧温度是当前的主要研究课题。同时为了提高电容器的性能．要求改进瓷料的热稳定性；为了降低电容器的成本，需要采用贱金属电极。本文从这几方面叙述了目前世界上的进展情况，并指出了其发展趋势。     

Electrical properties of sputtered (Ba, Sr)TiO3 thin films prepared by two-step deposition method

The influence of two-step deposition on the electrical properties of sputtered (Ba,Sr)TiO₃ thin films was investigated. BST thin films with thickness 40 nm were deposited by a simple two-step radio frequency-magnetron sputtering technique, where the BST thin film consisted of a seed layer and a main layer. The dielectric constant was strongly dependent on the thickness of seed layer, but there was no dependence on deposition temperature of the seed layer. For a 2 nm seed layer, the dielectric constants were higher by about 29% than those of single-step BST thin films due to higher crystallinity and the leakage current was nearly the same as that of a single-step sample in bias voltage from −2 to 2.5 V. However, an improvement of the dielectric constant was not observed for samples having above 4 nm thick seed layers. A 40 nm thick BST film with 2 nm thick seed layer deposited by a two-step method exhibited a SiO₂ equivalent thickness of 0.385 nm and a leakage current density of 2.74 × 10⁻⁸A/cm²at+1.5V after post-annealing under an atmosphere of flowing N₂ for 30 min at 750°C.     

Influence of La-Mn-Al Co-Doping on Dielectric Properties and Structure of BST Thick Film

A new sol-gel process is applied to fabricate the BST (BaxSr1(xTiO3) sol and nano-powder of La-Mn-Al co-doping with Ba/Sr ratio 65/35, and the BST thick film is prepared in the Pt/Ti/SiO2/Si substrate. The powder and thick film are characterized by X-ray diffraction and transmission electron microscope. The influence of La-Mn-Al co-doping on the dielectric properties and micro-structure of BST thick film is analyzed. The results show that the La, Mn, and Al ions can take an obvious restraint on the growth of BaSrTiO3 grains. The polycrystalline particles come into being during the crystallization of thick film, which may improve the uniformity and compactness of thick film. The influence of unequal-valence and doping amount on the leakage current, dielectric loss, and dielectric property are mainly discussed. The dielectric constant and dielectric loss of thick film are 1200 and 0.03, respectively, in the case of 1mol% La doping, 2mol% Mn doping, and 1mol% Al doping.