Enhancing optical properties of nanocrystalline silicon films with air exposure

We report the effect of air exposure and deposition temperatures, T_d, on the optical property of nanocrystalline silicon (nc-Si). The nc-Si thin films were investigated by photoluminescence (PL), optical absorption, X-ray diffraction (XRD), Fourier-transform infrared (FTIR) absorption and Raman scattering. Experimental results show the structural change from an amorphous to a nanocrystalline phase at T_d=80 °C. In addition, it suggests that T_d low condition leads to the increase in the density of SiH-related bonds and a decrease in the average grain size, δ. The oxygen absorption peak increases with the air-exposure time. The PL exhibited two peaks at around 1.75–1.78 and 2.1–2.3 eV. The PL increases and blue shifts consistently with the decrease of δ and increase of oxygen content. The first peak may be related to nanocrystallites in nc-Si films and the origin of another one may be due to defect-related oxygen. Thus, by the plasma-enhanced chemical vapor deposition (PECVD) technique at low T_d, we can produce the nc-Si films with different grain sizes, causing the corresponding luminescent properties. The new method processes advantages of low deposition temperature and effective oxidation of nc-Si on inexpensive substrates, thus making it more suitable for developing low-cost array or flexible nc-Si optoelectronic devices.     

激光增进的半导体异质结外延生长

文章阐述了光辅助外延生长的基本原理,光辐射增强生长速率主要有：光分解、光催化和光的热分解三种机制;介绍其在半导体材料外延生长中的具体应用,包括降低温度、掺杂控制、原子层外延和选择性外延;分析了实验中光的作用以及对材料晶体质量和光电特性的影响,为生长高质量材料提供实验基础。     

双层金属布线中隔离介质淀积工艺研究

隔离介质淀积是微波硅功率器件双层金属布线工艺中的核心工序.从隔离介质结构层次的选取入手,通过理论分析,选取SiO2-Si2N4两层介质为最佳隔离介质结构;着重对隔离介质淀积工艺进行深入研究.通过实验对比分析,确定芯片的隔离介质淀积工艺条件,从而避免光刻胶、腐蚀液等物质残留在芯片内部,提高双层金属布线的可靠性.     

适用于沉积工艺的真空技术

半导体生产中的薄膜沉积工艺通常对真空泵的要求很严格。在该工艺中高故障率和停机现象较为普遍。iH真空泵是特别为应付恶劣的薄膜工艺环境所设计。阐述了iH系列干泵在LPCVD氮化硅工艺应用中的成功表现。     

Effect of deposition temperature on structural,optical properties and configuration of CdSe nanocrystalline thin films deposited by chemical bath deposition

CdSe nanoparticle thin films were deposited on glass substrates by the chemical bath deposition (CBD) method at low deposition temperature ranging from room temperature up to 50 °C while the pH of the bath was kept constant at 12.1. The structural and morphological variation were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) technique. The energy band gap and optical properties were characterized by the absorbance spectra. Rutherford backscattering spectroscopy (RBS) analysis reveals the excess of Cd rather than Se in depth profile along the thin film thickness. The prepared CdSe nanoparticles have cubic structure and by increasing the temperature the deposited films become continues, homogeneous and tightly adherent. The results also revealed that by increasing the deposition temperature from room temperature up to 50 °C, the band gap decreases from 3.52 eV up to 1.84 eV.     

平板显示器制造中用作精密淀积设备的喷墨印刷头

显示器设备制造商之间有着共同的发展计划,电子流体显色剂和喷墨印刷头的设计者们已成功实现了大型电子显示板平板显示器引导线制造中特制的喷墨印刷头的发展计划。这种喷墨印刷头正在被认作各种大面积液晶显示器制造工艺的精密淀积设备。现这种喷墨型设备的市场需求正在不断增长。对于通过单独整理每个喷嘴通道进行一个128喷嘴的压力式喷墨印刷头流体下降位置控制情况给予了介绍。这种印刷头用作大型电子显示板显示器引导线的制造,通过采用不同的印刷头便可使大面积衬底的生产率得到提高的机会。讨论了通过印刷头和系统设计提高生产率实质。其它的高技术市场为利用精密降落位置和降落量控制。并给出了采用喷嘴制作印刷电路极的一些例子。     

PECVD法低温形成新型SiO_xN_y薄膜的界面特性研究

研究了等离子体增强化学气相淀积（PECVD）方法低温形成新型SIOxNy薄膜的界面特性。研究侧重于PECVDSiOxNy薄膜良好界面特性的控制，探索出界面特性与微观组份、衬底工作温度、反应室气压、退火致密、金属化后退火的相互关系。同时给出了获取界面等特性优良的PECVDSiOxNy薄膜的最优化工艺条件，并对实验结果进行了理论分析与讨论。     

1．3μmInGaAsP／InPLD，SLD和LED的介质镀膜

简要叙述了介质镀膜对半导体激光器性能的影响。在１．３μｍＩｎＧａＡｓＰ／ＩｎＰ激光器（ＬＤ）、超辐射发光二极管（ＳＬＤ）和发光二极管（ＬＥＤ）上进行了大量的Ａｌ２Ｏ３和ＺｒＯ２减反射膜的工艺研究。结果表明，该减反射膜使激光器阈值电流增加，并将部分激光器变成了超辐射发光二极管。减反射膜还显著地改进超辐射发光二极管的性能，增加其输出功率。它也能导致发光二极管的输出功率的有效增加。     

离子镀光学薄膜的等离子体物理过程

应用等离子体物理理论研究了离子镀光学薄膜中等离子体作用过程，得到了不同偏压条件下射入基片表面的离子和电子流密度和能量，从而为离子镀膜工艺参数的正确设计提供了理论依据。     

烟雾颗粒沉降速度研究

分析了影响烟幕粒子沉降的因素，论述了烟幕材料沉降理论的新进展和计算模型，测试了几种不同粒度、密度的微球和鳞片烟幕粒子材料在静止大气中的沉降速度。