Tin Sensitization for Electroless Plating Review

Abstract

Tin sensitization prior to electroless plating improves deposition of metals on a variety of substrates. This review summarizes relevant characteristics of the tin sensitized substrates, pre-treatment of surfaces before tin sensitization, adhesion, one-and twostep tin sensitization processes, photo-selective metal deposition (PSMD), and mechanisms and applications of tin sensitization. Mechanistic improvements to tin sensitization such as addition of aged tin(IV) chloride, and application of accelerators to remove the stannous shell and expose the catalytic core are evaluated. The effect of ultra-violet (UV) light on oxidation of tin(II) sensitized surface are analyzed for PSMD. The application section concludes with examples of tin sensitization in recent use and their commercial relevance.

Controlled Deposition of Tin Oxide and Silver Nanoparticles Using Microcontact Printing

“…The histogram of heights provided by the vendor (Digital™ nanoscope II) does not provide uncertainties in the z-dimension, so the data analysis used constant data weighting. The analysis used >128 points after 3 point smoothing of the raw data (for large size clusters) to extract four parameters in Equation (5) and three parameters in Equation (6). Typical values of un-normalized χ with Equation (5) providing a consistently better fit than Equation (6).…”

“…Typically the EMD process entails sensitizing a substrate with a reducing agent followed by metal deposition in a solution containing metal ions and an additional reducing agent. EMD on dielectric substrates lends itself to patterning of metals, first achieved by photo-selective metal deposition [5][6][7][8] (PSMD) using UV light exposure and chemical solutions. PSMD has been employed to deposit copper, silver, and gold using palladium and tin catalysts.…”

“…  (6) In this expression, d is the dimensionality of crystal nucleation and C is an adjustable constant. For d = 2 or 3 the distribution qualitatively looks similar to the one shown in Figure 13.…”

Reductive spectrophotometry of divalent tin sensitization on soda lime glass

“…Such arrays support coupling between lattice diffraction with localized surface plasmons for use in functional waveguides [8], nanoantennae [9], enhanced fluorescence sensors [10], biosensors [11], or surface enhanced Raman spectroscopy (SERS) [12]. EL plating is commonly initiated by tin (II) sensitization followed by substrate activation and metallization [13]. Tin (II) behaves as a strong stabilizing and reducing agent to create catalytic sites with less than 20 atoms on glass substrates [4].…”

“…The effects of tin sensitization, and activation steps on EL plating along with substrate properties have been evaluated by Rutherford backscattering [21][22][23], radiochemical tracer analysis [24,25], Mossbauer spectroscopy [26], X-ray fluorescence spectrometry [27] and X-ray photoelectron spectroscopy (XPS) [28]. Challenges of these methods [13,29] underscore a need for rapid, in situ evaluation of tin (II) deposited during sensitization with respect to operational variables, e.g., sensitization time, analyte concentration, aqueous immersion, and acid content.…”