Improvement of the field emission characteristics of an oxidized porous polysilicon using annealed Pt/Ti surface emitter electrode

The field emission characteristics of an oxidized porous polysilicon were investigated with different annealing temperatures. Pt/Ti, Ir, and Au/NiCr were used as surface emitter electrodes, and Pt/Ti emitter showed highly efficient and stable electron emission characteristic compared with the conventional Au/NiCr electrode. Thin Ti layer played an important role in promotion of adhesion of Pt to SiO₂ surface and uniform distribution of electric field on the OPPS surface. Additionally, the Ti layer efficiently blocked the diffusion of emitter metal, which resulted in more reliable emission characteristics. Pt/Ti emitter annealed at 350 °C/1 h showed the highest efficiency of 3.36% at V_ps=16 V, which resulted from the improvement of interfacial contact characteristics of thin emitter metal to an oxidized porous polysilicon. Annealing above 400 °C showed that Pt/Ti and Ir emitter electrode were thermally more stable than Au/NiCr emitter.     

LPCVD系统淀积多晶硅薄膜的发雾分析

叙述了采用LPCVD系统淀积多晶硅薄膜的机理,分析了在淀积多晶硅薄膜过程中引起发雾的因素,指出了保持LPCVD系统的洁净能有效消除在淀积多晶硅薄膜过程中出现的发雾现象.     

多晶硅薄膜晶体管RPI模型的直流参数提取

多晶硅薄膜晶体管(TFT)在有源液晶显示器中的应用充分显示了它的性能优点。对多晶硅TFT进行模型分析和参数提取是理解多晶硅TFT工作原理和指导制备的有效途径。归纳并讨论了多晶硅薄膜晶体管RPI模型直流参数的提取策略。此参数提取步骤简单,并能准确地提取所有工作区的基本直流参数,如阈值电压、漏源区串联寄生电阻、有效沟道长度、迁移率等。参数提取的方法将为RPI模型的电路仿真提供有益的参考。最后,提出了改进RPI模型参数提取策略的方向,包括提高泄漏电流参数、迁移率参数的准确度等。     

多晶硅横向压阻灵敏度的统计分析

本文用统计方法对择优生长的多晶硅横向压阻进行了分析:计算了<100>、<110>、<111>、<211>、<221>、<311>、<331>等低指数晶向择优生长的P型和N型多晶硅横向平均晶粒压阻系数;采用全空间统计平均的方法,计算得到了晶向完全随机的多晶硅横向平均晶粒压阻系数;从欧姆定律和多晶硅晶粒特性出发,推导了多晶硅横向压阻灵敏度的表达式。通过实验测量了多晶硅横向压阻器件的灵敏度及其与角度的关系,证实多晶硅横向压阻灵敏度与器件倾角α符合sin2α的关系。将实验结果与理论分析的结果相比较后,得到了多晶硅的杨氏模量,这些结果表明多晶硅横向压力传感器具有实用价值,并为器件提供了优化的设计方案。     

超高速VLSI中多晶硅发射极晶体管串联电阻的测量

本文对目前流行的测量晶体管串联电阻的常规方法进行了理论分析和实验验证，结果表明，用常规方法测量多晶硅发射极晶体管串联电阻的误差很大。     

Characteristics of thin film transistors fabricated in polysilicon films deposited by plasma enhanced chemical vapor deposition

Thin-film transistors (TFTs) fabricated in polysilicon films deposited by plasma enhanced chemical vapor deposition (PECVD) were characterized. The transistors were fabricated using a low temperature process (i.e., <- 700° C). The characteristics of the devices were found to improve as the deposition temperature of the polysilicon film increased. The best characteristics (μ _FE of 15 cm²/V _s andV _TH of 2.2V) were measured in the devices fabricated in the film deposited at 700° C. The devices fabricated in the PECVD polysilicon films were compared to those fabricated in polysilicon films deposited by thermal CVD in the same reactor in order to decouple the effect of the plasma. A coplanar electrode structure TFT with adequate characteristics (μ _FE of 8 cm²/V _s) was also demonstrated in the PECVD polysilicon films.     

Effects of oxygen on crystallization of amorphous silicon films and polysilicon TFT characteristics

Oxygen ions were implanted into the amorphous silicon film deposited at 540°C in order to study the effects of oxygen on the solid phase crystallization of silicon films. The resulting films were investigated using transmission electron microscopy, x-ray diffraction (XRD), and also by measuring the electrical characteristics of polycrystalline silicon thin film transistors (TFTs) fabricated in the crystallized films. The development of {111} texture as a function of annealing time is similar to films implanted with Si, with higher oxygen samples showing more texture. Transmission electron microscopy shows that the grain size of completely crystallized films varies little with oxygen concentration. The electrical performances of TFTs are found to degrade with increasing oxygen dose. The trap state density increases from 5.6 × 10¹²/cm² to 9.5 × 10¹²/cm² with increasing oxygen dose. It is concluded that for a high performance TFT, oxygen incorporation in the Si film should be kept to 10¹⁹/cm³ or less.     

多晶硅副产物四氯化硅的综合利用技术

前言 随着传统非再生能源石油、天然气、煤等的大量使用带来的温室效应破坏性作用的不断显现,加上长期过渡开采已经引发的资源枯竭,全球已经开始担忧能派安全问题,使得原油的价格在近几年特别是2007年以翻番的速度上升,所引发的问题已经超过石油危机年代。     

a-Si:H薄膜的再结晶技术及Si膜的Raman光谱分析

论述了非晶硅薄膜的几种主要再结晶技术,着重指出了各种晶化技术已取得的研究成果、优缺点、有待进一步研究的内容及其在多晶硅薄膜太阳电池工业生产中的应用前景.另外,还讨论了通过Raman光谱求纳晶硅薄膜的晶粒尺寸和结晶度的方法.     

异质结n＋多晶硅/n型4H-SiC欧姆接触的制备

从理论和实验的角度研究了n型4H-SiC上的多晶硅欧姆接触.在P型4H-SiC外延层上使用P 离子注入来形成TLM结构的n阱.使用LPCVD淀积多晶硅并通过P 离子注入及扩散进行掺杂,得到的多晶硅方块电阻为22Ω/□.得到的n 多晶硅/n-SiC欧姆接触的比接触电阻为3.82×10-5Ω·cm2,接触下的注入层的方块电阻为4.9kΩ/□.对n 多晶硅/n-SiC欧姆接触形成的机理进行了讨论.