Page 460 - Book Hosokawa Nanoparticle Technology Handbook

APPLICATIONS 4 MICROELECTRONICS PACKAGING BY METAL NANOPARTICLE PASTES
Attention has also been paid to the SERS sensor in [3] A.E. Neeves, M.H. Birnboim: J. Opt. Soc. Am. B, 6,
recent years. The sensor provides information of 787–796 (1989).
vibration and rotation in a molecule, so that details in [4] J. Homola, S.S. Yee and G. Gauglitz: Sens. Actuators
molecular structures are available. The SERS spec- B, 54, 3–15 (1999).
troscopy was found in the 1970s, and many studies [5] B. Liedberg, K. Johansen: Affinity Biosensing
have revealed that the origin of the large enhancement Based on Surface Plasmon Resonance Detection, in:
is attributed to two reasons [9]: one is the main reason K.R. Rogers, A. Mulchandani (eds.). Affinity
that a large electric field is produced in a rough silver
surface and the other is an additional reason that Biosensors Techniques and Protocols, Humana
enlarged molecular vibration upon adsorption of mol- Press, Totowa, NJ, pp. 31–54 (1998).
ecules on a silver surface. Recently a huge enhance- [6] K. Kajikawa: Protein Nucleic Acid Enzyme, 49,
ment of the SERS signal has been found in a system 1772–1776 (2004) (in Japanese).
of aggregated silver nanoparticles, and Raman spec- [7] Y. Okahata, H. Furusawa: Protein Nucleic Acid
troscopy from a single molecule has been reported Enzyme, 49, 1754–1758 (2004) (in Japanese).
[10–12]. Substrates that provide a large SERS signal [8] K. Mitsui, Y. Handa and K. Kajikawa: Appl. Phys.
have been developed [13]. These efforts enable us to Lett., 85, 4231–4233 (2004).
perform Raman spectroscopy without using special [9] K. Kneipp, H. Kneipp, I. Itzkan, R.R. Dasari and
techniques. Also portable Raman systems have been M.S. Field: Chem. Rev., 99, 2957–2975 (1999).
reported [14, 15].
In summery, LPR in metallic nanoparticles provides [10] S. Nie, S.R. Emory: Science, 275, 1102–1106 (1997).
many potential applications for optical sensors. The [11] H. Yu, E.J. Bjereld, M. Kaell and L. Borjesson: Phys.
fields are wide, such as chemistry, biology, medical, Rev. Lett., 83, 4357–4360 (1999).
genome engineering, materials science, and electronics. [12] Y. Maruyama, M. Ishikawa and M. Futamata: J. Phys.
Chem. B, 108, 673–678 (2004).
[13] N. Hashimoto, N. Ishikawa and A. Nakajima: Chem.
References
Phys. Lett., 413, 78–83 (2005).
[1] C.F. Bohren, D.R. Huffman: Absorption and [14] A.J. Sommer, S.A. Stewart: Appl. Spectrosc., 53,
Scattering of Light by Small Particles, Wiley, New 483–488 (1999).
York, pp. 335–380 (1983). [15] M.A. Young, D.A. Stuart, O. Lyandres, M.R.
[2] M. Fukui, M. Ohtsu: Hikarinanotekunoroginokiso, Glucksberg and R.P. Van Duyne: Can. J. Chem., 82,
Ohmsha Ltd., pp. 69–105 (2003) (in Japanese). 1435–1441 (2004).

APPLICATION 4
4 MICROELECTRONICS PACKAGING BY METAL NANOPARTICLE PASTES

1. Conductive paste technique and metal conductive metallic thin film. However, the firing
nanoparticle paste temperature of the conventional conductive pastes is
over 550 C, limiting the usage of the pastes to the
In the field of microelectronics packaging, conduc- glass and ceramics substrates.
tive paste technique is usually used for the forma- On the other hand, much attention has been paid
tion of various electronic components such as to metal nanoparticle pastes including metal
conductive circuits, electrodes, resistors, and nanoparticles with several nanometer to dozens of
dielectrics. Conventional technique of conductive nanometer size as a new technology available for
pastes is mainly thick film pastes composed of down-sizing and flexibility of the electronic compo-
metal powders with several micrometers to submi- nents. Decreasing the diameter of metal particle, the
crometer size and organic compounds. Using con- surface energy increases to become unstable com-
ductive pastes, the electronic circuit patterns are pared with the bulk metal. Usually, metal nanoparti-
figured on a substrate by screen printing or dispens- cles prepared by various methods are capped by
ing method, and so on, and then dried and fired to organic protecting groups to control the growth of the
decompose the pastes and to remove organic addi- particles and the particle size [1, 2]. Fig. 4.1 shows the
tives such as dispersants and coherence agents. As a transmission electron microscope (TEM) photograph
result, metal particles are melted and fused to afford of gold nanoparticles prepared by gas evaporation

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