退火对Ge诱导晶化多晶Si薄膜结晶特性的影响

本文采用磁控溅射法, 衬底温度500 ℃下在硅衬底上分别制备具有Ge填埋层的a-Si/Ge 薄膜和a-Si薄膜, 并进行后续退火, 采用Raman光谱、X射线衍射、原子力显微镜及场发射扫描电镜等对所制薄膜样品进行结构表征. 结果表明, Ge有诱导非晶硅晶化的作用, 并得出以下重要结论: 衬底温度为500 ℃时生长的a-Si/Ge薄膜, 经600 ℃退火5 h Ge诱导非晶硅薄膜的晶化率为44%, 在相同的退火时间下退火温度提高到700 ℃, 晶化率达54%. 相同条件下, 无Ge填埋层的a-Si薄膜经800 ℃退火5 h薄膜实现晶化, 晶化率为46%. 通过Ge填埋层诱导晶化可使在相同的条件下生长的非晶硅晶薄膜的晶化温度降低约200 ℃. Ge诱导晶化多晶Si薄膜在Si(200)方向具有高度择优取向, 且在此方向对应的晶粒尺寸约为76 nm. 通过Ge诱导晶化制备多晶Si薄膜有望成为制备高质量多晶Si薄膜的一条有效途径.     

H2对Ar稀释SiH4等离子体CVD制备多晶硅薄膜的影响

以SiH₄，Ar和H₂为反应气体，采用射频等离子体化学气相沉积方法在300℃下制备了低温多晶Si薄膜.实验发现，反应气体中H₂的比例是影响薄膜结晶质量的重要因素，在适量的H₂比例下制备的多晶Si薄膜具有结晶相体积分数高，氢含量低，生长速率快、抗杂质污染等特性. 关键词： 低温多晶Si薄膜 等离子体CVD 4')" href="#">Ar稀释SiH₄ 2比例')" href="#">H₂比例     

磁控共溅射低温制备多晶硅薄膜及其特性研究

多晶硅在光电子器件领域具有较为重要的用途。利用磁控溅射镀膜系统,通过共溅射技术在玻璃衬底上制备了非晶硅铝(α-Si/Al)复合膜,将Al原子团包覆在α-Si基质中,膜中的Al含量可通过Al和Si的溅射功率比来调节。复合膜于N₂气氛中进行350 ℃,10 min快速退火处理,制备出了多晶硅薄膜。利用X射线衍射仪、拉曼光谱仪和紫外-可见光-近红外分光光度计对多晶硅薄膜的性能进行表征,研究了Al含量对多晶硅薄膜性能的影响。结果表明：共溅射法制备的α-Si/Al复合膜在低温光热退火下晶化为晶粒分布均匀的多晶硅薄膜;随着膜中Al含量逐渐增加,多晶硅薄膜的晶化率、晶粒尺寸逐渐增加,带隙则逐渐降低;Al/Si溅射功率比为0.1时可获得纳米晶硅薄膜,Al/Si溅射功率比为0.3时得到晶化率较高的多晶硅薄膜,通过Al含量的调节可实现多晶硅薄膜的晶化率、晶粒尺寸及带隙的可控。     

射频溅射法制备3C-SiC和4H-SiC薄膜

利用射频溅射法在Si衬底上制备了SiC薄膜，并利用x射线衍射（XRD）和红外（IR）吸收谱对薄膜的结构、成分及化学键合状态进行了分析.XRD结果表明，低温制备的SiC薄膜为非晶相，而在高温下（＞800℃），薄膜呈现4HSiC和3CSiC结晶相.IR谱显示，溅射制备薄膜的吸收特性主要为Si—C键的吸收.此外，还利用原子力显微镜对薄膜的表面形貌进行了研究，并研究了样品的场发射特性. 关键词： 射频溅射 SiC薄膜 结构 表面形貌 场发射     

利用等离子体辅助脉冲磁控溅射实现 多晶硅薄膜的低温沉积

本文报道了利用电感耦合等离子体辅助中频直流脉冲磁控溅射在温度300 ℃ 以下沉积氢化多晶硅薄膜的制备方法. 利用拉曼散射、X射线衍射、透射电子衍射和傅里叶红外光谱对多晶硅薄膜进行了表征. 详细研究了氢气在沉积过程中所起的作用, 并结合Langmuir探针和发射光谱等等离子体诊断方法, 对辅助等离子体源在多晶硅薄膜制备过程中所起到的作用进行了讨论.     

直流辉光等离子体辅助热丝CVD法沉积金刚石薄膜

采用直流辉光等离子体助进热丝化学气相沉积（CVD）的方法，低温（550－620℃）沉积得到晶态金刚石薄膜，经X射线衍射谱（XRD），扫描电子显微镜（SEM）分析表明，稍高气压有利于金刚石薄膜的快速，致密生长。     

衬底材料对制备立方氮化硼薄膜的影响

较系统地研究了不同衬底材料对制备氮化硼薄膜的影响。用热丝增强射频等离子体CVD法,以NH3,B2H6和H2为反应气体,在Si,Ni,Co和不锈钢等衬底材料上,成功生长出高质量的立方氮化硼薄膜,还用13.56MHz的射频溅射系统将c-BN薄膜沉积在Si衬底上,靶材为h-BN(纯度为99.99％）,溅射气体为氩气和氮气的混合气体,所得到的氮化硼薄膜中立方相含量高于90%,用X射线衍射谱和傅里叶变换红谱对样品进行了分析表明,衬底材料与c-BN的晶格匹配情况,对于CVD生长立方氮化硼薄膜影响很大,而对溅射生长立方氮化硼薄膜影响不大。     

氢气稀释比例对多晶硅薄膜微观结构和沉积特性的影响

利用电感耦合等离子体增强化学气相沉积法(ICP-PECVD)直接在普通玻璃衬底上低温沉积多晶硅薄 膜,主要研究了不同氢气稀释比例对薄膜沉积特性和微观结构的影响。采用 X 射线衍射仪(XRD)、拉曼光谱仪和 扫描电子显微镜(SEM)表征了在不同氢气比例条件下所制备多晶硅薄膜的微结构、形貌,并对不同条件下样品的 沉积速率进行了分析。实验结果表明：随着混合气体中硅烷比例的增加,薄膜的沉积速率不断增加;晶化率先增 加,后减小;当硅烷含量为4.8%时,晶化率达到最大值67.3%。XRD 和 SEM 结果显示多晶硅薄膜在普通玻璃衬 底上呈柱状生长,且晶粒排列整齐、致密,这种结构可提高载流子的纵向迁移率,有利于制备高效多晶硅薄膜太阳能电池。     

激发频率对高氢稀释下纳米晶硅薄膜生长特性的影响

利用等离子体增强化学气相沉积技术,在高氢稀释条件下,研究不同激发频率对纳米晶硅薄膜生长特性的影响.剖面透射电子显微镜(TEM)分析结果显示,不同激发频率下制备的纳米晶硅薄膜晶化区均呈锥状结构生长,但13.56 MHz激发频率下制备的纳米晶硅薄膜最初生长阶段存在非晶态孵化层,即纳米晶硅薄膜的形成经历了由非晶态孵化层到晶态结构层的转变.而高激发频率(40.68 MHz)下硅纳米晶则能直接在非晶态衬底上生长形成.Raman谱和红外吸收谱测量结果表明高激发频率(40.68 MHz)下制备的纳米晶硅薄膜不但具有较高     

X射线荧光光谱法与电感耦合等离子体-原子发射光谱法联用测定土壤、水系沉积物、岩石中21种主、次和痕量元素

建立了X射线荧光光谱-电感耦合等离子体-原子发射光谱法(XRF-ICP-AES)联用技术测定土壤、水系沉积物和岩石中21种主、次和痕量元素的方法.采用复合熔剂熔融制样法,X射线荧光谱法测定其中的主量元素Al、Ca、Fe、Mg、K、Na、Si.熔融玻璃样片经(ψ)=10%(体积分数,下同)的HNO3超声波振荡提取,电感耦...     

Room-temperature anomalous Hall effect and magnetroresistance in (Ga, Co)-codoped ZnO diluted magnetic semiconductor films

This paper reports that the(Ga,Co)-codoped ZnO thin films have been grown by inductively coupled plasma enhanced physical vapour deposition.Room-temperature ferromagnetism is observed for the as-grown thin films.The x-ray absorption fine structure characterization reveals that Co 2+ and Ga 3+ ions substitute for Zn 2+ ions in the ZnO lattice and exclude the possibility of extrinsic ferromagnetism origin.The ferromagnetic(Ga,Co)-codoped ZnO thin films exhibit carrier concentration dependent anomalous Hall effect and positive magnetoresistance at room temperature.The mechanism of anomalous Hall effect and magneto-transport in ferromagnetic ZnO-based diluted magnetic semiconductors is discussed.     

Effect of potantiostatic waveforms on properties of electrodeposited NiFe alloy films

The influence of the deposition potentials applied in continuous and pulse waveforms on the properties of the electrodeposited NiFe alloy films have been investigated. The films were grown on (100) textured polycrystalline copper substrates. During growth, the films were characterized by recording the current-time transients. The composition of samples was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The analysis results revealed that the Fe content in the films decreases as both the deposition potential and the film thickness increase. The X-ray patterns showed that the films have face centred cubic (fcc) structure as their substrates and the (111) texture. The magnetic characteristics of films studied by a vibrating sample magnetometer (VSM) were found to vary depending on the type of the deposition (pulse or continuous) and the thickness of samples. The easy axis is in the film plane for all samples.     

PLD方法制备的纳米Fe/Al薄膜的结构及应力分析

 采用PLD方法制备了Fe/Al合金薄膜，研究了Fe/Al合金薄膜的物相、结构、应力等。研究表明薄膜的沉积速率随着衬底温度的升高而降低。原子力显微镜（AFM）图像显示，薄膜表面平整、致密且光滑，均方根粗糙度小于1 nm。等离子体发射谱（ICP）表明Fe/Al原子比为1∶1。X射线小角衍射（XRD）分析表明薄膜中的物相是Al_0.5Fe_0.5，Al_0.5Fe_0.5晶体具有简单立方结构(SC)，晶格常数为0.297 nm，平均晶粒尺寸为81.74 nm，平均微畸变为0.007 6。     

The optoelectronic properties of silicon films deposited by inductively coupled plasma CVD

Hydrogenated amorphous and microcrystalline silicon films were deposited by inductively coupled plasma chemical vapor deposition (ICP-CVD) at low substrate temperatures using H₂-diluted SiH₄ as a source gas. High-density plasma generated by inductively coupled excitation facilitates the crystallization of silicon films at low temperatures, and microcrystalline silicon films were obtained at the substrate temperature as low as 180 °C. The columnar structure of the films becomes more and more compact with an increase of their crystallinity. The reduction of hydrogen content in the films causes a narrowing of the optical bandgap and an enhancement of the absorption with increasing the substrate temperature. The microcrystalline silicon films show two electronic transport mechanisms: one is related to the density of state distribution in the temperature region near room temperature and the other is the variable range hopping between localized electronic states close to the Fermi level below 170 K. A reasonable explanation is presented for the dependence of the optoelectronic properties on the microstructure of the silicon films. The films prepared at a substrate temperature of 300 °C have highly crystalline and compact columnar structure, high optical absorption coefficient and electrical conductivity, and a low hydrogen content of 3.8%.     

Preparation of thin Si:H films in an inductively coupled plasma reactor and analysis of their surface roughness

An important concern in the deposition of Si:H films is to obtain smooth surfaces. Herein, we deposit the thin Si:H films using Ar-diluted SiH₄ as feedstock gas in an inductively coupled plasma reactor. And we carry a real-time monitor on the deposition process by using optical emission spectrum technology in the vicinity of substrate and diagnose the Ar plasma radial distribution by Langmuir probe. Surface detecting by AFM and surface profilometry in large scale shows that the thin Si:H films have small surface roughness. Distributions of both the ion density and the electron temperature are homogeneous at h = 0.5 cm. Based on these experimental results, it can be proposed inductively coupled plasma reactor is fit to deposit the thin film in large scale. Also, Ar can affect the reaction process and improve the thin Si:H films characteristics.     

Synthesis of carbon nitride films by low-power inductively coupled plasma-activated transport reactions from a solid carbon source

Thin films of carbon nitride were prepared by low-power inductively coupled plasma chemical vapor deposition from a solid carbon source by utilizing transport reactions. The maximum deposition rate achieved was 10 nm/min and depended mainly on the substrate position in the reactor. The nitrogen fraction in the films was not so sensitive to the process parameters and was at about 0.5 for all experiments as measured by Auger electron spectroscopy (AES) and elastic recoil detection (ERD) analysis. The chemical bonding structure studied by Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) showed the presence of triple, double and single bonds between carbon and nitrogen atoms. Received: 12 May 1999 / Accepted: 12 May 1999 / Published online: 24 June 1999     

Segregations and desorptions of Ge atoms in nanocomposite Si_(1-x)Ge_x films during high-temperature annealing

Nanocomposite Si_(1-x)Gex films are deposited by dual-source jet-type inductively coupled plasma chemical vapor deposition(jet-ICPCVD).The segregations and desorptions of Ge atoms,which dominate the structural evolutions of the films during high-temperature annealing,are investigated.When the annealing temperature(Ta)is 900~℃,the nanocomposite Si_(1-x)Gex films are well crystallized,and nanocrystals(NCs)with the core-shell structure form in the films.After being annealed at 1000~℃(above the melting point of bulk Ge),Ge atoms accumulate on the surfaces of Ge-rich films,whereas pits appear on films with lower Ge content,resulting from desorption.Meanwhile,voids are observed in the films.A cone-like structure involving the percolation of the homogeneous clusters and the crystallization of NCs enhances Ge segregation.     

Study on SiN and SiCN film production using PE-ALD process with high-density multi-ICP source at low temperature

SiN and SiCN film production using plasma-enhanced atomic layer deposition (PE-ALD) is investigated in this study. A developed high-power and high-density multiple inductively coupled plasma (multi-ICP) source is used for a low temperature PE-ALD process. High plasma density and good uniformity are obtained by high power N₂ plasma discharge. Silicon nitride films are deposited on a 300-mm wafer using the PE-ALD method at low temperature. To analyze the quality of the SiN and SiCN films, the wet etch rate, refractive index, and growth rate of the thin films are measured. Experiments are performed by changing the applied power and the process temperature (300–500 °C).     

Magnetic properties of Mn-doped ZnO diluted magnetic semiconductors

A series of Mn-doped ZnO films have been prepared in different sputtering plasmas by using the inductively coupled plasma enhanced physical vapour deposition. The films show paramagnetic behaviour when they are deposited in an argon plasma. The Hall measurement indicates that ferromagnetism cannot be realized by increasing the electron concentration. However, the room-temperature ferromagnetism is obtained when the films are deposited in a mixed argon-nitrogen plasma. The first-principles calculations reveal that antiferromagnetic ordering is favoured in the case of the substitution of Mn^2＋ for Zn^2＋ without additional acceptor doping. The substitution of N for O （NO^-） is necessary to induce ferromagnetic couplings in the Zn-Mn-O system. The hybridization between N 2p and Mn 3d provides an empty orbit around the Fermi level. The hopping of Mn 3d electrons through the empty orbit can induce the ferromagnetic coupling. The ferromagnetism in the N-doped Zn-Mn-O system possibly originates from the charge transfer between Mn^2＋ and Mn^3＋ via NO^-, The key factor is the empty orbit provided by substituting N for O, rather than the conductivity type or the carrier concentration.