印制线路板内层黑氧化前处理微蚀液的研制

研制出一种新型印制线路板内层黑氧化前处理微蚀液,其配方为:100g/LH2SO4,25g/LH2O2,0.4g/L稳定剂A(含羟基的有机酸),0.4g/L促进剂A(同稳定剂A),0.5g/L脂肪胺EO-PO嵌段聚合物。讨论了温度及铜离子浓度对微蚀速率的影响。测试表明,在高浓度铜离子(Cu2 质量浓度25g/L)存在的情况下,微蚀速率较稳定,可达到1.4μm/min以上,且微蚀后铜表面较平整均匀,可完全满足内层黑氧化前处理的生产要求。     

不同膨润剂对聚丙烯塑料膨润效果的研究

采用不同膨润体系对聚丙烯塑料(PP)进行膨润处理,在一定的条件下对膨润后的PP基体进行微蚀处理。通过研究膨润剂种类、膨润剂含量和膨润时间对PP基体微蚀效果的影响,确定合理的膨润条件。研究结果表明：膨润温度为70℃,纯四氯化碳(CCl₄)膨润处理80 min,膨润和微蚀处理后,PP基体表面形成分布均匀致密的微小孔洞,PP基体表面接触角由91.3°降低为57.9°,亲水性明显改善,微蚀效果较好。因此,CCl₄是一种性能优良有效的PP基体表面膨润体系。     

ABS工程塑料表面无铬二氧化锰微蚀粗化的研究

采用由磷酸、硫酸、二氧化锰组成的微蚀液对ABS工程塑料表面进行微蚀。通过测量开路电位,分析了微蚀液的组成与其氧化能力的关系。讨论了微蚀液中磷酸和硫酸的体积比对ABS塑料表面形貌、表面接触角及其与铜膜之间粘结强度的影响。微蚀液的最佳组成为:MnO260g/L,V(H3PO4):V(H2SO4)=1.5:1。ABS塑料经最佳组成的微蚀液处理20min后,其表面形成大量均匀致密的微孔,其表面对水的接触角为39.5°,与铜镀层的粘结强度为0.60kN/m。     

膨润条件对聚碳酸酯塑料表面微蚀效果的影响

采用无铬、低污染的MnO2–H2SO4–H2O体系对PC(聚碳酸酯塑料)表面进行微蚀。以微蚀后PC基板的表面形貌、水接触角及其与铜层间的粘结强度为性能指标,研究了膨润液中NMP(N甲基吡咯烷酮)含量及微蚀时间对微蚀效果的影响。用NMP体积分数为80%~85%的膨润液于35°C下对PC处理5min后,再在含30g/LMnO2、12.3mol/LH2SO4的胶体溶液中70°C微蚀时,可得到较理想的微蚀效果,其水接触角可低至33.8°,基板与铜层的粘结强度可高达0.88kN/m。     

超声辅助增强聚碳酸酯表面无铬微蚀效果研究

在超声振荡辅助下,利用环境友好的Mn O2–H2SO4–H3PO4–H2O四元微蚀体系对聚碳酸酯(PC)进行微蚀处理。研究了微蚀体系中2H OV∶3 4H POV∶2 4H SOV和超声辅助时间对PC基板表面形貌、表面粗糙度及其对铜镀层粘结强度的影响。结果表明,经超声辅助微蚀处理后,PC基板表面形成大量致密、均匀的微孔。超声辅助不仅能够提高PC基板表面微孔的均匀性,降低基板表面的平均粗糙度,而且能够增大PC基板的氧化速率,增强基板表面的亲水性,从而使PC能够在较低的表面粗糙度和较强的表面亲水性下获得对铜镀层较高的粘结强度。最优的微蚀处理工艺条件为:2H OV∶3 4H POV∶2 4H SOV=1∶1∶(3.2~3.4),Mn O2 80 g/L,温度60°C,超声辅助微蚀时间10 min。     

环氧树脂板化学镀铜前微蚀和激光活化工艺优化

先用碱性高锰酸钾溶液对环氧树脂板进行微蚀,再均匀涂覆由硫酸铜和次磷酸钠组成的活化液,接着利用激光诱导技术在基板表面获得具有催化活性的铜微粒,最后进行化学镀铜。重点研究了微蚀温度、微蚀时间和激光扫描速率对铜镀层覆盖率的影响。结果表明,当微蚀温度为70°C,微蚀时间为14 min,激光扫描速率为12 mm/s时,活化效果最佳,后续化学镀铜层的覆盖率达到100%,表面均匀致密,结合力良好。     

光亮微蚀剂PM-05的研制

随着欧盟ROSH指令的实施,印制电路板(PCB)的可焊性涂覆层由热风整平(HASL)工艺转向化学沉镍金、化学沉锡和化学沉银工艺,同时表面安装技术要求化学镀层具有很高的平坦性,针对这一需求我们开发了一种铜面光亮微蚀剂PM-05。本文着重介绍了该药水的使用工艺流程,并对该药剂的性能进行测试。通过测试数据表明,PM-05是一种理想的铜面光亮微蚀剂。     

紫外辅助增强ABS与镀层间粘结性的研究

在紫外光照射下利用环境友好的H_2SO_4-MnO_2-H_3PO_4-H_2O四元微蚀体系对丙烯腈-丁二烯-苯乙烯共聚物(ABS)进行微蚀处理,研究了紫外光功率及紫外光照射时间对ABS表面形貌、表面亲水性及粘结强度的影响。结果表明,在H_2SO_4-MnO_2-H_3PO_4-H_2O四元微蚀体系中,当微蚀时间为10 min,紫外光照射功率分别为300 W和500 W,照射时间分别为8 min和6 min时,ABS基板中的聚丁二烯相与聚丙烯腈-苯乙烯相之间存在较大的微蚀速率差,ABS基板表面的微孔数量多、致密且均匀,ABS基板的表面由憎水性变为强的亲水性,粘结强度分别为1.08 kN/m和1.10 kN/m,相较于四元微蚀体系在55℃无紫外光辅助照射下微蚀处理10 min后所得的0.64 kN/m,粘结强度显著提高。     

塑料基体表面无铬粗化的研究进展

总结了丙烯腈-丁二烯-苯乙烯共聚物表面无铬微蚀的研究现状,归纳了几种不同微蚀方法对塑料基体的处理效果;介绍了一种环境友好型的二氧化锰-硫酸微蚀体系。通过该体系处理的塑料表面不仅粗糙度增大而且亲水性基团含量增加,镀层与基体之间的粘结强度可以达到1.19kN/m。     

膨润条件对聚碳酸酯塑料表面微蚀效果的影响

研究了膨润液中N-甲基吡咯烷酮含量、膨润温度、膨润时间对微蚀效果的影响,以微蚀后聚碳酸酯基板的表面形貌、水接触角及基板之间与镀铜层间的粘结强度对微蚀效果进行评定。结果表明,当聚碳酸酯基板先用70%N-甲基吡咯烷酮-15%乙二醇乙醚-15%水溶液在40℃膨润处理7 min后,再经80 g/L MnO2,V(H3PO4)∶V(H2O)∶V(H2SO4)=1∶1∶3.5的胶体溶液70℃处理10min,可得到较理想的微蚀效果,其表面接触角可低至25.2°,基板与镀铜层的粘结强度可达0.93kN/m。     

Improved shape evolution of copper interconnects prepared by jet-stream etching

In the preparation of copper interconnects in the conductor pattern of a printed circuit board (PCB), wet etching processes are commonly adopted for creating patterns of high-density interconnects. Currently available techniques of immersion and spray etching could lead to poorly shaped wires due to complex flow fields or the disturbing puddling effect. A modified technique of arrayed jet-stream etching was developed in this work, aiming at producing well-defined copper interconnects on a PCB in a significantly shorter time. The results were appealing in that copper interconnects of 35/140 μm (thickness/width) exhibiting etching factors of greater than 6 were obtained in 20 s, much better than the conventional ones with etching factors of 3 to 5 and etching times of at least 2 min. In addition, uniformly etched copper interconnects with less than 20 μm undercuts were observed on one etching line. One additional point to note is that no banking agents or inhibitors as commonly seen in conventional etching techniques were needed in this new processing method.     

铜表面复合超疏水薄膜的制备及表征

该文利用自组装技术,在HNO3(质量分数6.5%)刻蚀的铜表面制备了(3-巯基丙基)三甲氧基硅烷(MPTS)与正辛基三乙氧基硅烷(OS)的复合纳米薄膜,并通过红外光谱对膜结构进行了分析。通过扫描电子显微镜确定了该复合膜具有纳米-微米级粗糙结构;静态接触角达158.6°,滚动角为3°,表明该膜具有超疏水性能;盐水实验证明该复合膜有效地提高了铜的耐腐蚀能力。     

The formation of hydrophobic and corrosion resistant surfaces on copper and bronze by treatment in myristic acid

The surface of freshly etched copper and bronze samples was modified by immersion in ethanol solutions of myristic (tetradecanoic) acid. Modification resulted in the formation of hydrophobic layers with contact angles up to 141°. Two kinds of surface structure were observed. The modified surface of copper was covered by a uniform layer containing nano-grains or knitted-like structure, whereas the modified surface of bronze was covered by a layer with lamellate patterns and nano-grains. The corrosion properties of bare and modified copper and bronze surfaces were tested by potentiodynamic polarization experiments in 0.014 M Na₂SO₄ + 0.024 M NaHCO₃ solution. The deduced effectiveness of corrosion inhibition by the modified layers on copper and bronze was up to 97 and 68%, respectively. Modification of the surface by immersion in an ethanol solution of myristic acid appears to be a promising treatment for improving the corrosion resistance of copper. The same treatment was not very effective when used on bronze.     

Quality enhancement of copper oxide thin film synthesized under elevated gravity acceleration by two-axis spin coating

Two-Axis spin coating as a new modified technique is employed to enhance the quality and surface leveling of thin films. The modified technology utilizes a synthetic centrifugal force perpendicular to the surface which generates an elevated gravity acceleration while spreading the coating on the entire wafer surface. In this paper, copper acetate sol-gel is coated by conventional and Two-Axis spin coating techniques. The coated layers are sintered in an air furnace at 275 °C. The fabricated layers are characterized by GIXRD, EDX, AFM and SEM devices. Wettability and Surface Free Energy (SFE) of sintered films using the contact angle technique are measured, and evaluated by the Owens-Wendt method. XRD and EDX spectra show a higher intensity of copper oxide phase using Two-Axis spin coating technology. AFM micrographs showed an improvement in the surface leveling within the Two-Axis spin coated layer. A comparison between the SFE of conventional and Two-Axis spin coated layers shows an increase in SFE of the layer synthesized under 200g artificial gravity acceleration.     

Adhesion Improvement of ABS Resin to Electroless Copper by H2SO4–MnO2 Colloid with Ultrasound-Assisted Treatment

The adhesion strength between electroless copper and acrylonitrile-butadiene-styrene (ABS) resin can be improved significantly by an environmentally friendly etching system containing H₂SO₄–MnO₂ colloid as a replacement for conventional chromic acid etching solutions. In this paper, the effects of the H₂SO₄ concentration and ultrasound-assisted treatment (UAT) on the surface roughness and adhesion strength were investigated. When the H₂SO₄ concentration was 11.8～12.7 M, good etching was obtained. With UAT, many uniform cavities formed on the ABS surface with the average surface roughness (R _a) and maximum roughness (R _max) of ABS substrates decreasing from 386 and 397 nm to 278 and 285 nm, respectively, which were much lower than that etched by CrO₃–H₂SO₄ colloid (420 and 510 nm, respectively). The average adhesion strength increased from 1.29 to 1.39 kN/m, which was close to that obtained with chromic acid etching treatment (1.42 kN/m). The surface contact angle measurement indicated that the density of the polar groups on the ABS surface increased with increasing time of UAT. The results indicated that surface etching with UAT not only improved the uniformity of cavities, but also enhanced the oxidation rate of ABS resin, which in turn resulted in greater adhesion strength and a lower surface roughness.     

Photolithography of polytetrafluoroethylene for adhesion

Irradiation of polytetrafluoroethylene (PTFE) with Mg(Kα) X-rays is shown to protect the surface against the chemical etching steps used to prepare PTFE for adhesion. Preirradiated etched samples of PTFE have adhesion strengths to epoxies of less than 3% of that for nonirradiated etched samples. The major portion of this decrease in adhesion strength occurs for X-ray exposures of less than 10 min and failure in every case occurs in PTFE and not in the bonded transition region. XPS measurements (20 Å sampling depth) show little difference in F content between irradiated and nonirradiated samples, but thermal desorption shows increasing short chain fluorocarbon desorption with irradiation time. These results are consistent with previous studies showing that irradiation produces free radicals that lead to branching and/or crosslinking, and a surface rich in low molecular weight fluorocarbons. The crosslinked surface is resistant to deep (10,000 Å) chemical attack and rich in short chain fluorocarbons; both effects are expected to lead to weak adhesive bonding.     

Kinetics of copper dissolution and deposition in aqueous sulphate solution

Galvanostatic single-pulse, rotating-disc and chronopotentiometric measurements on etched polycrystalline copper electrodes in semimolar mixed solutions of CuSO₄, MgSO₄ and H₂SO₄ at 25°C have yielded kinetic parameters and specific rate data for either of the two consecutive charge-transfer steps of the Cu(I)/Cu(II) electrode. The ion-transfer step Cu/Cu(I), but not the electron-transfer step Cu/Cu(II), depends on a surface factor for crystal growth and demolition. Some information on this factor is obtained. Comparisons are made to the solid Ni/Ni(II) electrode and to the liquid Cu(Hg)/Cu(II) electrode.     

Printed silver nanowire antennas with low signal loss at high-frequency radio

Silver nanowires are printable and conductive, and are believed to be promising materials in the field of printed electronics. However, the resistivity of silver nanowire printed lines is higher than that of metallic particles or flakes even when sintered at high temperatures of 100-400 °C. Therefore, their applications have been limited to the replacement of transparent electrodes made from high-resistivity materials, such as doped metallic oxides, conductive polymers, carbon nanotubes, or graphenes. Here we report that using printed silver nanowire lines, signal losses obtained in the high-frequency radio were lower than those obtained using etched copper foil antennas, because their surfaces were much smoother than those of etched copper foil antennas. This was the case even though the resistivity of silver nanowire lines was 43-71 μΩ cm, which is much higher than that of etched copper foil (2 μΩ cm). When printed silver nanowire antennas were heated at 100 °C, they achieved signal losses that were much lower than those of silver paste antennas comprising microparticles, nanoparticles, and flakes. Furthermore, using a low temperature process, we succeeded in remotely controlling a commercialized radio-controlled car by transmitting a 2.45 GHz signal via a silver nanowire antenna printed on a polyethylene terephthalate film.     

In situ atomic force microscopy investigation of copper behaviour and polypyrrole deposition from salicylate medium

The morphological modifications accompanying the electrochemical behaviour of copper in aqueous salicylate solution, have been investigated by in situ atomic force microscopy (AFM), with the purpose of elucidating the role of salicylate ions during polypyrrole electrodeposition onto this oxidisable metal.The surface changes revealed by in situ AFM images, are in agreement with previous attributed electrochemical processes, namely the formation of a non-uniform passivating layer, which does not completely block the copper surface. The presence of such layer prevents a strong anodic copper dissolution without hinder the pyrrrole oxidation. Pyrrole electropolymerization process has been also followed in real-time by AFM, and occurs through the formation of a first polymer layer, which follows the initial copper surfaces irregularities and is characterized by polypyrrole round nodules of different sizes, whereas for thick polymer films the influence of substrate defects is not detected.     

Development of a microchannel catalytic reactor system

The purpose of this article is to demonstrate the applicability of microreactors for use in catalytic reactions at elevated temperatures. Microchannels were fabricated on both sides of a silicon wafer by wet chemical etching after pattern transfer using a negative photoresist. The walls of the reactor channel were coated with a platinum layer, for use as a sample catalyst, by sputtering. A heating element was installed in the channel on the opposite surface of the reactor channel. The reactor channel was sealed gas-tight with a glass plate by using an anodic bonding technique. A small-scale palladium membrane was also prepared on the surface of a 50-Μm thick copper film. In the membrane preparation, a negative photoresist was spin-coated and solidified to serve as a protective film. A palladium layer was then electrodeposited on the other uncovered surface. After the protective film was removed, the resist was again spin-coated on the copper surface, and a pattern of microslits was transferred by photolithography. After development, the microslits were electrolitically etched away, resulting in the formation of a palladium membrane as an assemblage of thin layers formed in the microslits. The integration of the microreactor and the membrane is currently under way.