| Summary: | 碩士 === 國立海洋大學 === 材料工程研究所 === 89 === Traditional IC fabrication , aluminum usually used to deposition the metal line. But When metal line developing to 0.25μm、0.18μm. Traditional PVD-Al already can’t conform IC fabrication requirement. Copper has higher melting point and lower specific resistanc than aluminum, So copper can availably to prevent RC delay and increase electro migration competency. Now copper line fabrication usually use electroplating. This article discussion use electroless plating method to deposition metal line and diffusion barrier thin film. We wish use the advantage of electroless plating to overcome some problem in IC fabrication, such as the diffusion barrier ability and filling ability, there is another matter, because electroless plating having selectivity ability, hance We use the characteristic could simplify the procedure of IC fabrication.
The electroless plating is one of chemistry deposition methods, The reduction reaction transfer of electron electron between of catalyst species, then reaction the metal ion to metal. And the metal atom(Ni、Co、Pt、Pd) having catalyst competency make sure the second reaction can proceeding, after formation a layer of atoms. So if the adhere between substrate and thin film is nice, and the stability in liquid is enough, It is not difficulty control the thickness of thin film.
Now we use the chemical dynamics to study what conditions can influence the initial rate(Ri) like changing the ions quantity and the temperature, last We found Ri = 586 [Cu2+]0.676 [HCHO]0.162 [EDTA4-]-0.210exp[-38.69×103（in J/mole‧K）/ RT], This result are suitable for some coverage. The effect of plating are not the same in different Cu2+、HCHO、and EDTA4 ion concentration.
Another, Co-P use to resist Copper diffusion to substrate, We found pass by 500℃ annealing 5 min the interface between diffusion barrier and copper line also exist. And We use XRD to define composites of thin film, After 650℃ RTA, cobaltic atoms consume by phosphoric become Co2P, and Cu3P phase is not exit. In order make Co-P thin film become amorphous, We add W to attain purpose.
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