金刚石化学镀铜及还原处理研究

为改善金刚石和金属基体的润湿性,采用两种不同还原剂的配方在金刚石颗粒上进行化学镀铜,并在氢气气氛中对镀铜膜的金刚石进行还原处理。通过扫描电镜和X射线衍射仪研究了不同还原剂和不同还原温度对镀铜膜的微观形貌和成分的影响。结果表明:采用硼氢化钾比甲醛做还原剂化学镀铜效果好,用硼氢化钾做还原剂镀的铜膜晶粒为纳米微晶结构;在氢气氛中还原温度为300℃时氧化亚铜被还原成铜,在该温度下还原的铜膜表面平整均匀,晶粒无长大现象,对薄膜形貌影响较小;还原的镀铜金刚石呈紫红色,随还原温度的升高其外表由光亮逐渐变的暗淡,铜膜晶粒逐渐长大,薄膜的粗糙度也随之变大。     

Evaluation of the corrosion protection behaviour of poly(neutral red) films on passivated copper

The corrosion protection behaviour of poly(neutral red) (PNR) films on copper electrodes has been investigated using open circuit measurements, Tafel plots and electrochemical impedance spectroscopy. Pure copper electrodes were initially passivated in sodium oxalate, salicylate or hydrogen carbonate solution, to inhibit copper dissolution at potentials where neutral red monomer oxidation occurs, before its electropolymerization by potential cycling. The corrosion inhibition by these films was tested in 0.10 M KCl solution. It was found that, after long immersion times (96 h), the best protection efficiency was with PNR films formed on copper passivated in oxalate solution.     

Si(100)衬底上(110)取向La_(2/3)Sr_(1/3)MnO_3薄膜的制备与性能

用脉冲激光沉积法在Si(100)衬底上制备了(110)择优取向的La2/3Sr1/3MnO3薄膜,研究了环境氧压对薄膜结晶度、取向、表面形貌和微结构的影响。结果表明:10Pa氧压下沉积的薄膜具有高结晶度的(110)择优取向,晶粒分布均匀,晶粒分布均匀,表面均方根粗糙度Rrms为1.35 nm。与无明显择优取向的薄膜相比,(110)择优取向的La2/3Sr1/3MnO3薄膜具有较高的饱和磁化强度(Ms)、金属-绝缘体相变温度(TM-I)和较低的电阻率(ρ)。     

微波功率对(100)晶面取向金刚石薄膜制备的影响

以H2和CH4的混合气体为气源,使用实验室自制10 kW新型装置,采用微波等离子体化学气相沉积法(MPCVD)在Si(100)基体上沉积金刚石薄膜,然后采用扫描电镜(SEM)、Raman光谱以及XRD光谱,以得到表面形貌、样品质量和晶面取向等信息,由此获得微波功率对金刚石薄膜取向的影响。结果表明,微波功率对金刚石膜的质量、表面形貌和晶面取向都有明显地影响,随着微波功率升高,金刚石薄膜的形貌变得规则,薄膜中Isp3/Isp2由1.52提高到6.58,其沉积晶面的I(100)/I(111)由0.38提高到3.93。当微波功率为4 900 W时,所得沉积样品晶面以(100)为主,形貌规则,纯度很高。     

Chemical Vapor Deposition of Iridium and Rhodium Coatings from Hydridotetrakis(trifluorophosphine) Complexes

Chemical vapor deposition (CVD) of iridium and rhodium coatings using hydridotetrakis(trifluorophosphine) complexes as the precursor is presented. These inorganic, volatile, carbon- and oxygen-free compounds undergo a decomposition reaction to form highly pure iridium and rhodium metallic films on molybdenum substrates in the CVD reactor at growth temperatures as low as 450°C. The dependences of the deposition process and characteristics of the iridium and rhodium coatings have been investigated.     

On the stress in plasma-deposited a-SiC:H films

Amorphous hydrogenated silicon-carbon alloys were deposited by plasma chemical vapour deposition on silicon substrates from gas mixtures of SiH₄-C₂H₂ and SiH₄-C₂H₄ at temperatures ranging from 150 to 350°C. The solid composition of the films depends on the reactive gas ratio and the deposition temperature. The total residual stress, which is always compressive, depends on the solid composition and shows a minimum at an Si/C ratio of about unity. This behaviour is attributed to a change in the microstructure of the coatings. With an increase in the deposition temperature the total stress decreases owing to hydrogen release and annealing of implantation damage. Annealing of the films leads firstly to lower compressive stress and ultimately to tensile stress.     

Thermal plasma chemical vapor deposition of wear-resistant, hard Si-C-N coatings

Wear-resistant, hard Si-C-N coatings were synthesized in a triple torch plasma reactor using a thermal plasma chemical vapor deposition process. In this reactor, three dc plasma torches were angled so that their jets converge to form a highly chemically reactive region at the substrate. Vaporized hexamethyldisilazane (HMDSN) was injected through a central injection probe, while nitrogen or hydrogen gases were added through the torches to the argon plasma.Various dissociation, recombination and intermediate reactions were considered to determine what major species exist in the gas phase during the deposition of Si-C-N films. Reactant flow rates were varied to evaluate the thermodynamic equilibrium compositions across a linear temperature profile above the substrate and to identify the species that lead to the production of wear-resistant, hard Si-C-N films.A series of experiments were conducted at low HMDSN flows (∼ 1 sccm) and varying hydrogen and nitrogen flows. Films were characterized by micro X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Indentation tests were conducted on the polished film cross-sections, while wear tests were carried out on the film surfaces. At substrate temperatures below 1000 °C, amorphous Si-C-N films were deposited, while higher temperatures produced crystalline composite films of α- and β-Si₃N₄ and α- and β-SiC. Films produced with hydrogen at low HMDSN flows displayed non-columnar morphology and therefore had higher wear-resistance, indicating the benefit of low reactant-to-plasma gas flow concentrations on film growth. At low HMDSN flows, low nitrogen-to-hydrogen ratios had also shown an increase in film linear density. Small variations in mechanical properties and wear were observed between films grown under low N:H flow ratio conditions (smooth film surfaces). Wear-resistance of films with columnar structures from high N:H conditions was significantly lower, while the hardness was unobtainable. This result indicates the importance of film morphology on mechanical performance.     

热处理对两种铜膜结合强度的影响

采用PVD和CVD技术制备Cu/TiN/PI试样，研究表明，TiN薄膜可以有效地阻挡Cu向PI基板内部扩散，CVD工艺制备的Cu膜内部残余应力很小，Cu膜有相对高的结合强度；而PVD制备的Cu膜，在有TiN阻挡层存在的情况下，Cu膜内存在拉应力，拉应力降低了Cu膜结合强度，300℃退火可以消除膜内残余应力，结合强度提高。     

电流密度对电沉积铜膜剩余电阻率的影响

为了获得1.3 GHz功率耦合器的镀铜膜,研究不同电流密度和沉积时间对镀铜膜剩余电阻率(RRR)的影响。电流密度分别为1、1.5和2 A/dm~2,沉积时间为1～6 h,讨论了铜膜RRR值、微观形貌、表面粗糙度和织构随镀层厚度的变化。结果表明,随着电流密度减小和沉积时间延长,表面粗糙度变大,铜膜RRR值增大。在电流密度为1和1.5 A/dm~2下沉积的铜膜,随着沉积时间的增加,晶胞结节变大,(111)晶面的织构系数增加,铜膜RRR值变大。在电流密度为2 A/dm~2下沉积的铜膜中含有孔洞缺陷,导致铜膜的RRR值显著下降。硬X射线自由电子激光装置的1.3 GHz功率耦合器的铜膜采用电流密度为1 A/dm~2,沉积时间为4 h的镀铜工艺,其铜膜RRR值、铜膜与基体结合力、高低温适应性以及微波功率均满足实际工程应用。     

超声波对Ta/SiO2/Si基板置换活化法化学镀铜的影响

采用置换活化法,以PdCl2/BOE/HNO3溶液对Ta/SiO2/Si基板进行活化,然后在基板上成功实现化学镀Cu薄膜。应用场发射扫描电子显微镜(FESEM)、X射线衍射(XRD)等方法,研究了活化时间及超声波对化学镀Cu薄膜表面形貌和结构的影响。结果表明,在化学镀Cu过程中没有引入超声波时,随着活化时间由30 s增加到150 s,Cu膜覆盖率逐渐降低;在引入超声波以后,随着活化时间的增加,Cu膜覆盖率始终很高。XRD分析表明,引入超声波以后,Cu(111)和(200)峰的衍射强度明显增加,当活化时间为60 s时,Cu(111)和(200)峰的强度比I(111)/I(200)达到4.53。对具有沟槽的Ta/SiO2/Si基板进行化学镀Cu的结果表明,引入超声波,可以明显改善对沟槽的填充效果