Applications to Magnetic Recording and Microelectronic Technologies

Abstract

Early applications of electrodeposition in manufacturing were mainly confined to situations where relatively thick polycrystalline metal deposits were needed. These included protective or sacrificial metal layers for corrosion protection, decorative applications, and situations where metal coatings with specific mechanical properties were needed [1]. However, development of theoretical foundations in electrochemical engineering and electrometallurgy and the sophistication of the tools used for electrodeposition have contributed to widespread electrodeposition in high-tech industry where more rigorous thickness control of the deposit is required. Nowadays, electrodeposition is recognized as a mature deposition method for the fabrication of magnetic thin-film heads [2, 3] and in microelectronics and microelectromechanical system (MEMS) technologies [4][5][6][7]. The most recent developments suggest that electrodeposition is an attractive fabrication process for many emerging fields of nanotechnology. These new applications make the future of electrodeposition research a seemingly interesting and quite exciting endeavor.In this chapter we will review the most important electrodeposition processes used for fabrication of magnetic recording heads and in microelectronics technology. The most important parameters, criteria, and phenomena controlling the deposit morphology and properties are highlighted and discussed using the examples from the authors' own work and from the work of other prominent groups around the world. MAGNETIC RECORDINGNowadays electrodeposition is used for the fabrication of many important parts of magnetic recording heads, including magnetic shields and poles, Cu coils, and for connecting Cu studs, leads and pads, Au interconnects, and nonmagnetic gaps and coatings. Some of these electrodeposition processes and bath chemistries were adopted from other technologies as a common practice. However, the fabrication of the writing pole in magnetic recording heads has been the most important manufacturing step where electrodeposition has gained its fame as a cost-effective, reliable, and high-throughput operation (Fig. 27.1a). Over the years, the development of magnetic reader technologies, recording medias and the geometry of the magnetic recording process have posed many challenges that electrodeposition had to meet in order to stay competitive with other deposition methods. The common requirement for the alloys for magnetic pole fabrication is that they have low coercivity (softness), low magnetostriction (l % 0), and relatively high magnetic moment. The electrodeposition process of these alloys has to be scalable with high-throughput manufacturing with minimum effort in process control and reproducibility. The bath chemistry has to be stable over the time and compatible with other materials and processes used in through-mask fabrication.In the very beginning, the electrodeposited magnetic alloy for magnetic pole application was Ni 81 Fe 19 -Permalloy (inductive read heads)-with saturation magnetic fl...

Self-assembled nanostructured resistive switching memory devices fabricated by templated bottom-up growth

“…The positive Ni 2+ ions react with 2e − and are converted to metallic nickel (Ni 0 ) at the cathode surface. The nickel ions discharged at the cathode are thus replenished by those formed at the anode 24 . Electrochemical deposition was performed under the previously given conditions using the transferred AAO nanotemplate.…”

Editors' Choice—Reaction Kinetics of Metal Deposition via Surface Limited Redox Replacement of Underpotentially Deposited Monolayer Studied by Surface Reflectivity and Open Circuit Potential Measurements

“…The very details of these three protocols and their applications have been discussed elsewhere in the literature. 4,5,10 Still, more work is necessary to unravel the controlling phenomena of this deposition method and to properly define optimum conditions at which the true benefits of this method are fully exploited.…”

“…The very details of these three protocols and their applications have been discussed elsewhere in the literature. 4,5,10 Still, more work is necessary to unravel the controlling phenomena of this deposition method and to properly define optimum conditions at which the true benefits of this method are fully exploited.In many applications concerned with deposition of only a single monolayer of P or ultra-thin films such as core-shell catalyst synthesis for example 2,3,6 (P = Pt, Pd), the properties of deposited films are * Electrochemical Society Student Member. * * Electrochemical Society Member.…”

Underpotential and Electroless Pb Monolayer Deposition on Ru(0001)

“…[8][9][10][11] More recent applications include ML restricted deposition methods where UPD phenomenon serves as enabling process. [12][13][14][15][16] Along these efforts, a very exciting development has been demonstrated with the first reports of an electroless (e-less) Pb and Zn ML deposition phenomenon. [17][18][19][20] Detailed analysis of these results suggest that e-lessly deposited Pb ML has a UPD-like properties 18,19 and thus pertains to a wide variety of applications already demonstrated for its UPD counterpart.…”