Characterization of crystallographic properties of SMC poly Si using electron backscattered diffraction

Crystallographic properties of silicide mediated crystallization (SMC) polycrystalline silicon (poly Si) and excimer laser annealing (ELA) poly Si were studied by electron backscattered diffraction. Large‐grain sized poly Si with a large fraction of low‐angle grain boundaries was acquired by SMC, and small‐grain sized poly Si with high‐angle grain boundaries especially around 60° was acquired by ELA. The thin film transistor (TFT) device characteristics were investigated in view of short‐range crystallinity (pattern quality) and long‐range crystallinity (misorientation distribution) of the specimens. Short‐range crystallinity did not significantly affect the TFT device characteristics, and long‐range crystallinity considering the low energy level of special boundaries could be better related to the TFT device characteristics of poly Si.     

The low temperature polysilicon (LTPS) thin film MOS Schottky diode on glass substrate for low cost and high performance CO sensing applications

The Au/SnO₂/n-LTPS MOS Schottky diode prepared on a glass substrate for carbon monoxide (CO) sensing applications is studied. The n-LTPS (n-type low temperature polysilicon) is prepared by excimer laser annealing and PH₃ plasma treatment of an amorphous Si thin film on glass substrate. The developed Schottky diode exhibits a high relative response ratio of ∼546% to 100 ppm CO ambient under condition of 200 °C and −3 V bias. The response ratio is better than the reported SnO₂ based resistive type CO sensors of 100% and 37%, respectively on poly-alumina and glass substrates or comparable to 390% of Pt-AlGaN/GaN Schottky diode CO sensor. Thus, the Au/SnO₂/n-LTPS Schottky diode has the potential to develop a low cost high performance CO sensor.     

On the study of p-channel thin-film transistors fabricated by SLS ELA crystallization techniques

The electrical characterization, in terms of drain current, of SLS ELA p-channel polysilicon TFTs is investigated. The study was based on the DLTS technique. It was found that drain current is governed by trapping/detrapping mechanisms associated to poly-Si/SiO₂ interface states. This fact is in accordance with the results of stretched exponential analysis applied on switch-ON drain current transients. DC hot carrier measurements under worse ageing condition regime were also conducted. Threshold voltage and transconductance variation revealed that hole injection towards the gate oxide is the prevailing mechanism, while poly-Si/SiO₂ interface degradation seems to be minor.     

Characteristics of polycrystalline Si TFTs fabricated on glass substrates by excimer laser annealing with nickel-sputtered amorphous Si films

We have fabricated two kinds of thin film transistors (TFTs) on the glass substrates using polycrystalline silicon (poly-Si) thin films with small and large grain sizes processed by Excimer Laser Annealing (ELA) and carried out a comparative analysis. The grain size was controlled by nickel atom content in amorphous silicon (a-Si) thin films. With increasing grain size of poly-Si thin films, the carrier mobility increased from 40.8 to 54.4 cm²/V s and the absolute value of threshold voltage reduced from 2.1 to 1.5 V. The observed improvements in the electrical characteristics of poly-Si TFTs are attributed mainly to the reduction of defect density rendered by large grain size. These observations indicate that the sputtered nickel atom content in a-Si layer is a key parameter in determining the characteristics of ELA processed TFTs fabricated on the glass substrates.     

一种运动自适应去隔行技术及其VLSI结构

提出一种有效的运动自适应去隔行算法.该算法通过对同极性的相邻场进行运动检测,把插值点所处的区域分为快速运动区域、慢速运动区域和静止区域,对不同的区域采用不同的插值算法.在边缘检测方面,采用改进型ELA算法克服了传统的ELA算法处理水平边缘方面的不足,使边缘得到有效保护.与运动补偿算法相比,该算法计算复杂度较低,易于VL...     

4G时代的移动通信基站环评问题探讨

随着4G基站的大规模建设,4G基站的环境影响评价工作也越来越多,由于4G基站使用的是2GHz以上的频段,其信号衰耗远大于900M系统,但是现有的环境影响评价工作中没有考虑高频和低频的差别,所以本文对4G时代的移动通信基站环评问题进行了探讨,并提出了一种测试的方法。     

一种改进的运动自适应去隔行算法

在总结回顾各种去隔行算法的基础上,对运动自适应去隔行算法中的空域场内插值算法和运动检测算法做了改进。针对传统ELA算法对图像水平边沿处理的不足,添加了水平边沿检测,并加大了ELA窗口,使处理效果得到提升。另外提出了一种新的运动检测算法,使用领域窗口内带权重的4场隔场差值作为运动估计,同时加入了1个2维中值滤波器滤除由图像噪声而引起的运动检测噪点。仿真结果表明这两种算法的复杂度不高,因此易于硬件实现。     

一种基于改进型边沿线平均算法的去隔行设计

该文在原有边沿线平均去隔行算法的基础上设计和实现了改进型的边沿线平均算法。本系统包括rgb2yuv,edge_detection,Sif,yuv2rgb 4个模块,可调参数通过AMBA总线配置。其中Sif模块为本文设计的重点.本设计用VerilogHDL语言实现,同时并为此设计搭建了功能完备的Modelsim仿真环境,进行了仿真验证,最后用FPGA实现其功能。     

低温多晶硅薄膜的制备工艺研究

低温多晶硅薄膜是制备高性能薄膜晶体管的首选材料，由其制成的薄膜晶体管由于在平板显示器件驱动中所展现的优越性能而受到广泛关注。本文系统介绍了低温多晶硅薄膜的三种制备方法-金属诱导横向晶化法、准分子激光晶化法和电感耦合等离子体化学气相沉积法的原理和研究进展，比较了它们之间各自的优缺点，最后对该领域的发展前景进行了展望。     

低温多晶硅薄膜制备技术应用进展

系统介绍了金属诱导横向晶化法、准分子激光晶化法、触媒化学气相沉积法(Cat-CVD)以及电感耦合等离子体化学气相沉积法(ICP-CVD)制备低温多晶硅薄膜的原理及进展。对不同制备工艺的优势和不足进行了比较,重点讨论了Cat-CVD和ICP-CVD在实用化中需克服的技术问题。对上述制备方法的应用前景作了评述和展望。