磷掺杂比例对a-Si∶H薄膜太阳电池窗口层光电性能的影响

采用RF-PECVD法制备了磷掺杂氢化非晶硅(a-Si∶H)薄膜作为太阳电池窗口层.通过椭偏仪、Keithley 4200对所制备样品进行分析测试,研究了不同掺杂比例对非晶硅薄膜沉积速率、消光系数、折射率、光学带隙及电导率等的影响.实验表明:薄膜沉积速率随掺杂浓度升高先减小再增大;薄膜消光系数、折射率及禁带宽度随掺杂浓度升高呈现先减小后增大再减小的现象;电导率则先增大后减小再增大.     

RF等离子体聚合类聚氧化乙烯(PEO-like)功能薄膜研究

采用射频等离子体，以乙二醇二甲基醚（Ethylene Glycol Dimethyl Ether）为聚合单体，用氩气作为工作气体，合成类聚氧化乙烯（PEO-like）官能聚合物。实验采用连续和脉冲射频等离子体两种放电模式聚合PEO功能薄膜，研究了等离子体放电参数：等离子体放电功率、工作气压、放电模式（连续或脉冲）和聚合时对聚合物表面结构、官能团含量以及表面特性等影响。利用接触角测试仪、表面张力仪、傅里叶变换红外光谱（FTIR）、膜厚仪和X-射线光电子能谱（XPS）等多种手段对聚合薄膜的组成、结构和性能进行了表征。结果表明，较小的功率以及较长的脉冲条件下有利于EO基团的形成。     

PECVD法淀积氮化硼薄膜场发射特性研究

用 Ｂ２Ｈ６和 ＳｉＨ４作反应气体,通过射频等离子体增强化学气相淀积（ＲＦ－ＰＥＣＶＤ）方法,在 Ｓｉ（１００）面上沉积生长ＢＮ薄膜,用Ｓ－５２０扫描电子显微镜对所得薄膜进行观测,并用红外透射光谱测试分析了膜的成分。在室温、压力为 ８ × １０－４ Ｐａ条件下,对 ＢＮ薄膜的电流一电压特性进行测量,并得到了 Ｆｏｗｌｅｒ－Ｎｏｒｄｈｅｉｍ特性曲线,ＢＮ膜的场发射开启电场为９ Ｖ／μｍ,在电场３７．５ Ｖ／μｍ时,电流密度达到２４．８ ｍＡ／ｃｍ２。     

RF-PECVD制备类金刚石膜的研究

采用RF-PECVD法在锗(Ge)基片上沉积类金刚石(DLC)薄膜,研究了气体流量和气压对沉积区域均匀性的影响,以及基片厚度与沉积时间的关系。用拉曼光谱(Raman)分析DLC膜的结构组成,用傅立叶红外光谱仪(IR)对DLC膜的透过率进行了测量。结果表明,在气体流量为50 sccm,气压为10 Pa,功率800 W条件下薄膜厚度均匀性可达2.1%,极值透过率达62%。     

Properties of hydrogenated amorphous carbon films deposited by PECVD and modified by SF6 plasma

Hydrogenated amorphous carbon (a-C:H) films were grown at room temperature on glass and polished silicon substrates using RF-PECVD (Radio-Frequency Plasma Enhanced Chemical Vapor Deposition). Plasmas composed by 30% of acetylene and 70% of argon were excited by the application of RF signal to the sample holder with power ranging from 5 to 125 W. After deposition, the films were submitted to SF₆-plasma treatment for 5 minutes. SF₆ plasmas were generated at a pressure of 13.3 Pa by a RF power supply operating at 13.56 MHz with the output fixed at 70 W. The resulting films were characterized in terms of their molecular structure, chemical composition, surface morphology, thickness, contact angle, and surface free energy. During the SF₆ plasma treatment, fluorine species were incorporated in the film structure causing chemical alterations. The interaction of chemical species generated in the SF₆ plasmas with surface species was responsible for the decrease of the film thickness and surface energy, and for the increase of the film roughness and hydrophobicity.     

RF—PECVD聚合类聚乙烯氧（PEO—like）薄膜及其对血小板吸附性研究

本文采用平板式电容耦合射频(RF,13.56MHz)等离子体源,以乙二醇二甲基醚(Ethylene Glycol DiMethyl Ether)为聚合单体,氩气为辅助气体,在连续与脉冲射频等离子体两种放电模式下合成类聚乙烯氧(PEO-like)功能聚合薄膜.实验研究了等离子体放电参数:等离子体放电功率、工作气压、放电模式(连续或脉冲)和聚合时间等对聚合物表面结构、功能团含量、表面成分性能以及和血小板吸附等影响.利用接触角测定仪(WCA)、傅里叶变换红外光谱(FTIR)、原子力显微镜(AFM)等手段对聚合薄膜的结构、成分和形貌进行细致的分析.同时本文还进行体外细胞培养法,研究了类PEO功能薄膜对富血血小板的吸附,通过倒置显微镜观察细胞黏附的数量和形态变化.得到的结论为:采用RF-PECVD可以在较小功率的连续等离子体放电模式,或较长脉冲间隔的脉冲放电模式下得到结构稳定的PEO生物功能薄膜,所制备的PEO生物功能薄膜具有良好的抗血小板吸附性能.     

Characterization and tribological application of diamond-like carbon (DLC) films prepared by radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) technique

Diamond-like carbon (DLC) films were successfully prepared on glass substrates and surfaces of selenium drums via radio frequency plasma enhanced chemical vapor deposition method. The microstructure, surface morphology, hardness, film adhesion, and tribological properties of the films were characterized and evaluated by X-ray photoelectron spectroscopy, atomic force microscopy, and micro-sclerometer and friction-wear spectrometer. The results showed that DLC films have smooth surfaces, homogeneous particle sizes, and excellent tribological properties, which can be used to improve the surface quality of the selenium drums and prolong their service life.     

PECVD法低温制备纳米晶硅薄膜晶化特性的Raman分析

以SiH4与H2为气源,采用射频等离子体增强化学气相沉积技术,在较低的温度(200℃)和较高的压强(230 Pa)下,在普通的玻璃衬底上制备出沉积速率达8×10-10m/s,晶化率大于60%的纳米晶硅薄膜.利用Raman谱分析硅烷浓度和射频功率对纳米晶硅薄膜的晶化特性的影响.结果表明,薄膜的晶化率、沉积速率与硅烷浓度和射频功率存在着密切的关系.随着硅烷浓度的降低,即氢稀释率的提高,晶化率提高,而沉积速率随着射频功率的增大而增大.当硅烷体积浓度为1%、射频功率为70 W时,获得晶化率接近70%的优质纳米晶硅薄膜.     

Studies on the structural properties of SiO:H films prepared from (SiH4+CO2+He) plasma in RF-PECVD

A comprehensive report on the structural studies on SiO:H films prepared at high growth rate from He-diluted (SiH₄+CO₂) plasma has been presented and extraction of some intriguing ideas that deserve high relevance for the potential development of nano-crystalline hydrogenated silicon oxide (nc-SiO:H) films has been tried. Poly-hydrogenation has been found as inherent to increasing alloying of the network; however, the bonded H-content reduces linearly with the degree of oxygen incorporation, i.e., the solubility of H in the SiO:H network decreases as the O-content increases in the presence of He. This result happens to be opposite to the conventional H₂-diluted plasma condition and appears to be attractive as well. In addition, He-dilution contributes to a high growth rate of the material. Dynamic interaction of He* in the formation of activated oxygen atoms in the plasma and their efficient mobilization on the surface reaction process at the growing network induces abstraction of H from the SiH_n groups and the terminal H atoms are replaced by bridging O atoms to form the SiO:H network. Abstraction of H from the network being an essential criteria for developing nanocrystallinity and it being inherent to oxygenation in Si network when prepared from He-diluted (SiH₄+CO₂) plasma in PECVD, the process could provide an appropriate pathway for preparing nc-SiO:H structures for solar cells, from such plasma in suitable parametric conditions.     

p型微晶硅膜的研究及其在异质结太阳电池中的应用

首先采用射频等离子体增强化学气相沉积技术制备了电导率为0.13 S/cm、晶化率为50%的p型微晶硅,然后制备了μc-Si∶H(p)/c-Si(n)异质结太阳电池。初步研究了硼掺杂比、辉光功率密度、p型硅薄膜的厚度和氢处理时间等这些参数对电池开压的影响。在优化的工艺参数下得到异质结电池最大开路电压Voc为564mV。