Copper thin films

Figure 8.9. SEM image of a SILAR-grown copper thin film. The scale bar is 2 pin. Reprinted from Lindroos, Ruuskanen, Ritala and Leskela 2004. Thin Solid Films 460, Copyright (2004) with permission from Elsevier. 

A large class of coordination compounds, metal chelates, is represented in relation to microwave treatment by a relatively small number of reported data, mainly p-diketonates. Thus, volatile copper) II) acetylacetonate was used for the preparation of copper thin films in Ar — H2 atmosphere at ambient temperature by microwave plasma-enhanced chemical vapor deposition (CVD) [735a]. The formed pure copper films with a resistance of 2 3 pS2 cm were deposited on Si substrates. It is noted that oxygen atoms were never detected in the deposited material since Cu — O intramolecular bonds are totally broken by microwave plasma-assisted decomposition of the copper complex. Another acetylacetonate, Zr(acac)4, was prepared from its hydrate Zr(acac)4 10H2O by microwave dehydration of the latter [726]. It is shown [704] that microwave treatment is an effective dehydration technique for various compounds and materials. Use of microwave irradiation in the synthesis of some transition metal phthalocyanines is reported in Sec. 5.1.1. Their relatives - porphyrins - were also obtained in this way [735b]. 

When a crystal of pure silicon is embedded in copper and exposed to methyl chloride at 350° C., the interface between the two solids is seen to recede, and both copper and silicon are removed from the point at which they are in contact or in close proximity. The fact that either element is a catalyst for the removal of the other suggests that the mechanism depends upon mutual interaction, rather than upon adsorption, for example. To find out what happened to the copper, thin films of evaporated copper on glass were heated in an atmosphere of methyl chloride, and it was found that approximately half of the copper was transported in the form of a volatile labile compound, whereas the other half remained in the form of a transparent layer of crystals of cuprous chloride. The first step therefore appears to be... 

As an approach to a better understanding of adhesion mechanisms between polyimide and copper, we have studied the interaction between a set of model molecules for a polyimide and vapor deposited polycrystalline copper. Thin films and adsorbates of benzene, phthalimide, methyl-phthalimide, benzene-phthalimide, and malonamid, which are representative of separate parts of the polyimide repeat unit, were deposited in situ on clean copper and examined by means of X-ray and Ultraviolet photoelectron spectroscopy (XPS and UPS). In contrast to the previously observed bonding to the carbonyl oxygen in polyimide, as Cu is deposited on polyimide, our results show that most of these polyimide model molecules bond to Cu, through electron transfer, with the imide nitrogen atom as the primary reaction site. 

Shore G, Yoo W-J, Li C-J et al (2009) Propargyl amine synthesis catalysed by gold and copper thin films by using microwave-assisted continuous-flow organic synthesis (MACOS). ChemEur J 16 126-133... 

Steigerwald JM, Duquette DJ, Murarka SP, Gutmann RJ. Electrochemical potential measurements during the chemical-mechanical polishing of copper thin films. J Electrochem Soc 1995 142(7) 2379-2385. 

Padhi D, Yahalom J, Gandikota S, Dixit G. Planarization of copper thin films by electropolishing in phosphoric acid for ULSI applications. J Electrochem Soc 2003 150 10-14. 

J.M. Steigerwald, A Fundamental Study of Chemical Mechanical Polishing of Copper Thin Films, PhD Thesis, Rensselaer Polytechnic Institute, Troy, NY (1995). 

Figure 20. Copper deposit obtained at an overpotential of 1,000 mV. Time of electrolysis 10 s. Solution 0.15 M CuSC>4 in 0.50M H2SO4 temperature 18.0 1.0° C working electrode copper electrode previously covered by copper thin film. (Reprinted from Ref.18 with permission from Springer).

Analyzing the data in Figs. 19 and 22, we can notice that average diameters of holes formed at stationary vertical copper wire electrodes which were not previously covered by copper thin films were about two times smaller than those obtained by electrodeposition onto copper electrodes previously covered with a thin copper film. On the other hand, the number of the formed holes per square millimeter surface area ( regular holes ) was approximately five to ten times larger than the number of holes per square millimeter surface area obtained by electrodeposition onto copper electrodes with uniform thin copper films. 

You are attempting to grow a copper thin film on MgO. What characterization technique (or techniques) might you use to determine which of the three growth modes shown in Figure 13.14 occur What growth mechanism would you think would be most likely ... 

Tummala, R.R. and Ahmed, S. 1992. Overview of packaging of the IBM enterprise system/9000 based on the glass-ceramic copper/thin film thermal conduction module. IEEE Trans. Comp., Hybrids, and... 

Girolami GS, Jeffries PM, Dubois LH. Mechanistic studies of copper thin film growth from cui and cuii face P- Diketonates. J Am Chem Soc. 1993 115 1015-24. 

R. R. Tummala and S. Ahmed, Overview of Packaging for the IBM Enterprise System 9000 Based on the Glass-Ceramic Copper/Thin Film Thermal Conduction Module, 7EEE Trans, on Comp., Hybrids and Mfg. Tech., Vol. 14, No. 4, Dec. 1991, pp. 426-431. 

For instance, copper film 20 nm in thickness starts to disintegrate into drops at 883 K after 300 s, while at 743 K this process appears after 13000 s. The film 100 nm in thickness begins to dissociate at 1013 K after 420 s, while it also dissociates at 913 K, but after 9000 s. The disintegration of copper thin film occurs locally at any place of the sample and then spreads further frontally (Fig.lO). As a result, it is possible to distinguish three sample areas the area where the film remains continuous (Fig.lO (a)) the area where the film is totally dissociated into droplets (Fig.lO (e)), and the third one - narrow area or a front, where dispersion takes place (Fig.lO (b-d). 

Fig. 10. SEM photographs of the copper thin film at different stages of melting a) region of continuous film b) - d) region, where melting of film occurs e) region, where this film dissociated into droplets.

Fig. 11. Dependences of melting time in copper thin films of various thickness on heating temperature in a vacuum.

This result is a good indirect evidence that copper thin film at 800 C had properties of fluid and was in liquid state material is selected into spherical droplets, if surface wetting is absence, and fills the cavities, if there is good surface wetting. 

Fig. 17. Heterogeneous melting of the copper thin film deposited on the structure with trenches in Si02 coated by the layer of the amorphous Ta-W-N alloy (a) dispersion into droplets as a result of heat treatment at 1123 K and (b) flow in the trenches as a result of heat treatment at 1123 K owing to the introduction of the wetting 20 nm thick titanium layer between the Ta-W-N layer and the copper film.

Gromov, D.G., Gavrilov, S.A., Redichev, E.N. Ammosov R.M (2007). Kinetics of the melting-dispersion process in copper thin films. Physics of die Solid State, Vol. 49, No 1, p>p.l78-184, ISSN 1063-7834... 

Schadler, L. S. and Noyan, I. G. (1995), Quantitative measurement of distress transfer function in nickel/polyimide thin film/copper thin film structures. Applied Physics Letters 66, 22-24. 

Suresh, S., Nieh, T.-G. and Choi, B. W. (1999), Nanoindentation of copper thin films on silicon substrates, Scripta Materiala 41, 951-957. 

Weiss, D., Gao, H. and Arzt, E. (2001), Constrained effusion will creep in UHV-produced copper thin films, Acta Materialia 49, 2395-2403. 

N. L. Jeon, R.G. Nuzzo, "Physical and spectroscopic studies of the nucleation and growth of copper thin-films on polyimide surfaces by chemical-vapor deposition", Langmuir, 1995, 77, 341-355. 

Pao, T. Chen, Y.-Y. Chen, S. Yau, S.-L. 2013. In situ scanning tunneling microscopy of electrodeposition of indium on a copper thin film electrode predeposited on Pt(l 11) electrode. J. Phys. Chem. C117 ... 

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