Cu互连及其关键工艺技术研究现状

低介电常数材料和低电阻率金属的使用可以有效地降低互连线引起的延时。Cu因其具有比Al及Al合金更低的电阻率和更高的抗电迁移能力而成为新一代互连材料。论述了Cu互连技术的工艺过程及其研究发展现状。对Cu互连技术中的阻挡层材料、电化学镀Cu技术以及化学机械抛光技术等一系列关键工艺技术进行系统的分析和讨论。

Microstructure and electrical conductivity of electroless copper plating layer on magnesium alloy micro-arc oxidation coating

In order to impart electrical conductivity to the magnesium alloy micro-arc oxidation(MAO)coating,the electroless copper plating was performed.Effects of plating temperature and complexing agent concentration on the properties of the electroless copper plating layers were studied by measuring their microstructure,corrosion resistance and electrical conductivity.It was found that the optimized plating temperature was 60°C,and the most suitable value of the complexing agent concentration was 30 g/L.Under this condition,a complete and dense plating layer could be obtained.The formation mechanism of the plating layer on magnesium alloy MAO coating was analyzed.A three-stage model of the plating process was proposed.The square resistance of the plated specimen was finally reduced to 0.03Ω/□after the third stage.Through electroless copper plating,the MAO coated sample obtained excellent electrical conductivity without significantly reducing its corrosion resistance.

Anode oxidation of HCHO in THPED-containing electroless copper plating solution

The electrochemical mechanism of anode oxidation of HCHO in electroless copper plating solution with N, N, N′, N′-tetrakis(2-hydroxypropyl)ethylenediamine (THPED) was investigated by measuring cyclic voltammetry curves and anodic polarization curves. Three different oxidation peaks occur at the potentials of -0.62 V (Peak 1), -0.40 V (Peak 2) and -0.17 V (Peak 3) in the anode oxidation process of THPED-containing solution. The reaction at Peak 1, a main oxidation reaction, is the irreversible reaction of adsorbed HCHO with hydrogen evolution. The reaction at Peak 2, a secondary oxidation reaction, is the quasi-reversible reaction of adsorbed HCHO without hydrogen evolution. The reaction at Peak 3 is the irreversible oxidation of anode copper. The current density of Peak 1 increases gradually, that of Peak 2 remains constant and that of Peak 3 decreases with the increase of HCHO concentration. The current density of Peak 3 increases with the increase of THPED concentration and the complexation of THPED promotes the dissolution of anode copper.

Autocatalytic deposition of copper from modified electrolytes and its characteristics

The electroless deposition process of copper plating consisting of TEA and EDTA as complexing agents,paraformaldehyde as reducing agent,and 2-mercaptobenzothiozole as stabilizer and gelatin and animal glue as additives was investigated.The stability of the electroless copper solution was monitored by measuring the absorbance of the solution with a UV-Visible spectrophotometer and the solution was quite stable up to 15 h.The adhesion of copper films on mild steel foil was assessed by standard bend test and exhibited good adhesion.The XRD results indicate that the copper films have a(111) texture.Moreover,the additives suppress the predominant(111) plane crystal growth and increase the rate of(220) texture crystal growth.The crystal size of the copper films was calculated using the Scherrer formula from the predominant peak.SEM and AFM studies reveal that these two additives modify the crystal structure,grain size and surface morphology of the copper films.The cyclic voltammetry studies reveal that the additives are adsorbed on the electrode surface and inhibit the rate of deposition.Potentiodynamic polarization and electrochemical impedance studies reveal that the deposits produced in the presence of additives display higher corrosion resistance.

镀铜膜工艺在高功率输入耦合器中的应用

高功率输入耦合器是为自由电子激光装置的超导腔传输微波功率的部件。为了提高传输性能,需要在耦合器上镀铜膜。本研究基于2种不同镀铜膜工艺实验,通过EDS线扫描、粗糙度、XRD和残余电阻率(RRR)对比分析在室温(25℃)以及200、400、600和910℃等4种不同温度退火后镀铜膜的性能变化,确定出适合特殊环境条件下高功率输入耦合器波纹管内壁镀铜膜工艺。将这一工艺应用于1.3 GHz高功率输入耦合器镀铜膜。结果表明,铜膜与耦合器内表面的结合力、高低温适应性和微波能量传输效率都能很好地满足实际应用的要求。

对“简单的电镀实验”的思考

从反应机理、镀层金属结构特点等方面对“铁化学置换镀铜”的不足进行梳理,从而对比出“铁电化学镀铜”的优势。新人教版(2019年)教材增设了“简单电镀”的学生实验。通过查阅相关电镀工艺资料并结合实验,就中学教学实际,对该实验进行相关改进和完善,以期从理论与实践两个方面为实验教学提供些许借鉴与参考。

用于固态自旋量子调控实验的共面波导辐射结构的镀铜工艺实现

在固态自旋量子调控实验的微波系统中,辐射结构的传统实现方法存在制作成本较高,金属层结合力较弱等缺点。现有一种基于导电膜材料的电化学镀铜工艺方法可用于精度要求较低的辐射结构的实现。本文将该工艺应用到高频性能较好、磁场转化效率较高的共面波导辐射结构的实现中。由于共面波导辐射结构对工艺的精度要求较高,间接增加了其制作难度。本文对原有工艺方法做出了一系列改进,在完成了基于CST MWS软件的模型仿真以及工艺实现后,通过量子调控实验验证,在输入功率约为1 W的条件下,共面波导辐射结构在2.8 GHz频点处产生了强度约为6.58 Gauss的交变磁场。结果表明,本文的工艺方法可有效地实现共面波导辐射结构的制作,且性能较好。相比于传统微纳加工工艺,这种导电膜材料的电化学镀铜工艺方法缩减了步骤流程,较大幅度地降低了工艺实现的成本。

用于金刚石NV色心实验的辐射结构的设计与实现

在基于NV量子信息实验台上,我们需要对金刚石NV色心施加特定序列的微波射频脉冲信号。为了将特定序列的微波射频脉冲信号作用在样品上,我们利用具有损耗低、无截止频率等特点的槽线设计了一种新型平面电路辐射结构,能够将经过调制的微波射频脉冲信号转化为交变微波场,并作用在金刚石NV色心上,进而实现量子态调控。本设计基于的原理是利用传统槽线作为主传输线,T型槽线作为功分结构,Ω型圆环作为辐射结构,将主传输线中的一部分功率流馈入Ω型圆环内,辐射出较强的微波场。对比传统的光刻微纳工艺方法,本设计利用激光刻蚀及电化学镀铜工艺方法实现了辐射结构的低成本制作。通过网络分析仪等仪器设备测试后,该辐射结构目前已应用到基于NV量子信息实验台中,在高频2.8 GHz和低频7.1 MHz工作频率附近分别取得了约4.48 Gauss和48.49 Gauss大小的交变磁场。

Development of Electroless Copper and Gold Plating on Wood

The use of more and more electron products requires interior wood products to have the performance of electromagnetic shielding. One of the ways to realize it is to introduce the chemical plating which has already been developed in electron industry into wood processing. The paper clarifies the mechanism of electroless copper and gold plating and its application to wood. It emphasizes the development and technology of electroless copper and gold plating on wood. Meanwhile, it points out that it is highly feasible to take this technology into effect.