Metallized polyimide

Fig. 3.10. Experimental (dotted lines) and best-fit model (solid lines) IRSE spectra of a PLD-grown (0001) ZnO thin film on (001) silicon (panel (a), film thickness d 670 nm), and magnetron-sputtered ZnO thin films on metallized polyimide foil (panel (b), d 500nm) and on metallized glass (panel (c), d 30nm) [43]. ZnO phonon-mode frequencies, as obtained by best-model analysis, are marked by vertical arrows...

Polvimide-Metal Interfaces. Several technological applications including semiconductor packaging and metallization demand a reliable and durable adhesion properties of the metal films. In the development of multilayer devices consist of alternating layers of metal and polyimides several reliable techniques are needed to study both thin films and their interfaces. The usefulness of the nuclear scattering techniques to study the metallization and the associated interfacial elemental diffusion processes under the effects of various temperature and humidity treatments on the metal-polyimide systems, such as Al, Cu, N, and Au on Du Pont Kapton type H have already been reported (21., 22.). Only a couple of examples are presented here to illustrate the ERD application. 

X-ray photoelectron spectroscopy has been used to study the metal polyimide interface formed during room temperature metal deposition. Several mono-layers of Al, Au and Cu were sputter-deposited onto cured polyimide, to a thickness which permitted the observation of both polyimide and metal peaks. Deconvolution of core-level Cls, Nls and Ols polyimide peaks and A12p, Au4f and Cu2p3/2 metal overlayer peaks has demonstrated that chemical reaction occurs at the carbonyl sites for all these metals under the conditions used. In addition, the aromatic nature of the molecular structure at the interface is believed to decrease while the percentage of an isoimide-like component increases. 

Metal—Polyimide Interfaces Characterized by Secondary Ion Mass Spectroscopy... 

A more dramatic failure results in peel strengths of 0-10 g/mm and is characterized as an adhesive failure at the polyimide/metal oxide interface.This was the only failure mode observed in Ti and Zr films. Isotopically tagged water used with SIMS analysis shows that on annealing water reacts with the Ti with oxygen segregating to the metal/polyimide interface and hydrogen penetrating into the bulk of the Ti, in these samples. 

This paper describes a process for activating polyimide surfaces for electroless metal plating. A thin surface region of a polyimide film can be electro-chemically reduced when contacted with certain reducing agent solutions. The electroactivity of polyimides is used to mediate electron transfer for depositing catalytic metal (e.g., Pd, Pt, Ni, Cu) seeds onto the polymer surface. The proposed metal deposition mechanism presented is based on results obtained from cyclic voltammetric, UV-visible, and Rutherford backscattering analysis of reduced and metallized polyimide films. This process allows blanket and full-additive metallization of polymeric materials for electronic device fabrication. 

Thompson, D.S., Thompson, D.W., and Southward, R.E. (2002) Oxo-metal-polyimide nanocomposites. 2 enhancement of thermal mechanical and chemical properties in soluble hexafluoroisopropyUdene-based poly-imides via the in situ formation of oxo-lanthanide(III)-polyimide nanocomposites. Chemistry of Materials, 14,... 

Polyimide was used as a model material in studies of polymer metal interfaces where metal layers were formed by metallization, plasma deposition, chemical vapor deposition, electrochemical deposition, etc In most of the cases studied, the interpenetration of metal was so good that the metal layer could not be removed by any other means but abrasion. An investigation of interface, determined that the metal particles were found in the surface layers in diminishing quantities perpendicular to the surface and not, as expected, in the form of a sharp borderline between the metal and polymer. Some difficulties exist when metallized polyimides are used for chip production. These diffuse layers of metals complicate design and performance due to the gradients of conductivity which they produce. 

M. Aida. Metallized polyimide film and manufacturing method therefor. US Patent 7 241490, assigned to Mitsubishi Shindoh Co., Ltd. (Tokyo, JP), July 10, 2007. 

Polyifflides are commonly utilized as dielectric layers in the fabrication of microelectronic devices. Hence the metallization of polyimldes and the chemical and physical nature of metal-polyimide interfacea is of great technical importance and has been investigated extensively. Polyimldas perform well In microelectronic... 

Chu, Y. Z., Eiuming, C. J., Jeong, H. S., White, R. C. (1992). The adhesion strength of metal/polyimide and polyimide/silicon interfaces as determined by the blister test. In K. L. Mittal (Ed.), Metallized plastics 3 fundamental and applied aspects (pp. 347-364). Plenum Press, New York. 

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