Metals sputtering

Insulator sputtering is similar to the process described for metal sputtering. The only difference is that the source target is a dielectric film. There is less control of the chemical nature and quaUty of the film as compared to a CVD deposited film. Common sputtered films include siUcon nitride and sihcon oxide. 

Metallization can be applied by batch or continuous vacuum metallizing, sputtering and electroplating. 

SFM does not require any sample treatment like etching and metal sputtering but can visualize the native structure of the sample.97-100 SFM is, however,... 

In addition to high temperature bonding, a number of other bonding procedures have been reported (described in the Section 10.2). These procedures are most often used when additional functionality is to be incorporated into the chip. Most often this is metal sputtered onto the microchip architecture for electrodes or electrochemical detection, but could also include modification to the channel surface or incorporation of materials that cannot withstand the high bonding temperatures. In these cases, alternative cleaning methods may also need to be employed and the protocol for microchip bonding altered." ... 

Different metals sputter at different rates. However, when an alloy target is sputtered, the deposited film develops the same composition as the target material, as long as the target temperature is below that required for thermal diffusion. This is because the faster ejection of one element leads to the enrichment of the target s surface with elements that have lower sputter rates. Hence, differences in sputter rates are counteracted, and the deposited film obtains the same stoichiometry as the target. 

Andersen, H.H., Brunelle, A., Della-Negra, S., Depauw, J., Jacquet, D., Le Beyec, Y. (1998) Giant metal sputtering yields induced by 20-5000 keV atom gold clusters. Phys. Rev. Left.,5/1,5433-5436. 

Template synthesis is a relatively simple and easy procedure which has made the fabrication of rather sophisticated nanomaterials accessible to almost any laboratory. Template synthesis reqnires access to instmmentation capable of metal sputtering and electrochemical deposition. The characterization of the fabricated nanostructures can be done using instmmental techniques including spectrophotometry, voltanunetry, optical microscopy, atomic force microscopy, and electronic microscopies (scanning electron microscopy (SEM) and transmission electron microscopy (TEM)). 

Figure 16.2.5 Electrochemical template deposition of metals (A) scheme of the electrochemical cell and (B) sequence of the growth of the template for the preparation of single metal continuous nanowires (sequences 1-4) or segmented nanoparticles (sequences 1, 2, 5, and 6). Detailed steps (1) metal sputtering to provide a conductive layer for the subsequent electrodeposition (2) electrodeposition of the same metal to form the fibers (3) growth of the fibers (4) etching of the template (5) electrodeposition of another metal (6) composite structure after the etching of the foundation metal. Part (B) redrawn with permission from reference (25).

A very unique technique of etching the LC surface is adopted in which alkali metal hydroxide in presence of alkanolamine is used. This is followed by either metal sputtering or electroless coating to make adherent metal coating. 

Fig. 8 Photographs of (a) zigzag metal sputtered on PET substrate with the width of 26 mm and length of 90 mm and (b) PPy film electrochemicaHy deposited on the zigzag metal-PET tilm (Reproduced with permission from the Royal Society of Chemistry (Hara et al. 2004a))...

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