氮气或氧气气氛退火的氧化铪材料电荷泄漏情况研究

本文中, 使用开尔文探针显微镜,研究了不同退火气氛(氧气或氮气)情况下氧化铪材料的电子和空穴的电荷保持特性。与氮气退火器件相比,氧气退火可以使保持性能变好。横向扩散和纵向泄露在电荷泄露机制中都起了重要的作用。 并且,保持性能的改善与陷阱能级深度有关。氮气和氧气退火情况下,氧化铪存储结构的的电子分别为0.44 eV, 0.49 eV,空穴能级分别为0.34 eV, 0.36 eV。 最后得到,不同退火气氛存储器件的电学性能也与KFM结果一致。对于氧化铪作为存储层的存储器件而言,对存储特性的定性和定量分析,陷阱能级,还有泄漏机制研究是十分有意义的。     

Investigation of charge loss characteristics of HfO2 annealed in N2 or 02 ambient

The retention characteristics of electrons and holes in hafnium oxide with post-deposition annealing in a N2 or 02 ambient were investigated by Kelvin probe force microscopy. The KFM results show that compared with the N2 PDA process, the O2 PDA process can lead to a significant retention improvement. Vertical charge leakage and lateral charge spreading both played an important role in the charge loss mechanisms. The retention improvement is attributed to the deeper trap energy. For electrons, the trap energy of the HOS structure annealed in a N2 or 02 ambient were determined to be about 0.44 and 0.49 eV, respectively. For holes, these are about 0.34 and 0.36 eV, respectively. Finally, the electrical characteristics of the memory devices are demonstrated from the experiment, which agreed with our characterization results. The qualitative and quantitative determination of the charge retention properties, the possible charge decay mechanism and trap energy reported in this work can be very useful for the characterization of hafnium charge storage devices.     

基于垂直双轴结构太阳能光电跟踪系统研究

针对当前我国太阳能利用率的不足,提出了一种基于垂直双轴机械结构的太阳能光电跟踪系统,它利用2DU10系列硅光电池组成四象限光强传感器,通过低功耗单片机AT mega16L智能控制横向纵向步进电机42H4630转动,使四象限光强传感器法线方向始终正对太阳位置以接收最大太阳能.同时串口监控四象限电压输出,便于控制中心记录管理.该系统能够智能识别黑夜、阴雨天等阳光不充分的情形进入低功耗模式,避免吸收光能小于机动耗能.实现自动、精确、高效地太阳能光电跟踪.     

基于GSM网络的无线远程水表计量监控的研究

针对当前传统机械水表存在的不足与缺陷,提出了一种基于全球移动通信系统（GSM）短信息通信的无线水表,它采用YF-21水流量传感器,通过超低功耗单片机MSP430F149智能控制,由短信息TC35模块发射GSM短信息,其包含水流量计量信息,软件设置密码保护,实现远程、自动数据采集传输与计量。     

Ag-石墨烯纳米复合材料的室温制备及其结构分析

在室温条件下利用水合肼将氧化石墨烯和AgNO3还原获得Ag-石墨烯纳米复合材料,并利用X射线光电子能谱(XPS),X射线衍射(XRD),X射线能谱(EDX)及高分辨透射电镜(HRTEM)等方法对制备的纳米复合材料进行分析.结果表明:Ag-石墨烯复合材料中石墨烯的含氧官能团数量大幅降低,氧化石墨烯已被还原为石墨烯;Ag纳...     

Charge Loss Characteristics of Different Al Contents in a HfA10 Trapping Layer Investigated by Variable Temperature Kelvin Probe Force Microscopy

Kelvin probe force microscopy （KFM） technology is applied to investigate the charge storage and loss characteristics of the HfAlO charge trapping layer with various AI contents. The experimental results demonstrate that with the increase of AI contents in the HfAIO trapping layer, trap density significantly increases. Improvement of data retention characteristic is also observed. Comparing the vertical charge loss and lateral charge spreading of the HfAIO trapping layers, the former plays a major role in the charge loss mechanism. Variable temperature KFM measurement results show that the extracted effective electron trap energy level increases with increasing AI contents in HfAIO trapping layer, which is in accordance with the charge loss characteristics.     

基于无线传输的远程智能卡信息读写器的实现

现在,越来越多的场合用到智能卡,需要对其中的信息进行读写操作;同时,对智能卡读写设备的便携性和易用性等提出越来越高的要求.文中使用标准的智能卡读写器S1882I,通过RS232串行通信接口与自行研制的无线传输电台有效连接,从而实现了智能卡信息的远程无线传输,此外使用GPRS模块作为备用通信端口,可以实现重要信息与标准移动通信终端如手机之间的实时通信,非常适合临时性如应急等场所或者架设线缆不方便、成本高等时候使用.经测试,可以达到预期的功能要求.