Vacuum metallization

Vacuum Metalli ng Cycolac, Technical Report P135, Borg-Wamer Corp., Chicago, lU., 1980. 

Weil, F. C., Recent Developments in Vacuum Metal Coatings , Electroplating Meta Finish, 9, 6, 25 (1956)... 

In these processes, a special base coat is applied to the surface of the plastic product to be metallized. The product is then placed in a vacuum chamber in which a metallic vapor is created and deposited on the product. A protective clear top coat is then applied over the thin metal layer for abrasion and environmental resistance. The simplest vacuum metallizing processes use resistance heating to melt and vaporize the metal. 

From a reaction engineering viewpoint, semiconductor device fabrication is a sequence of semibatch reactions interspersed with mass transfer steps such as polymer dissolution and physical vapor deposition (e.g., vacuum metallizing and sputtering). Similar sequences are used to manufacture still experimental devices known as NEMS (for nanoelectromechanical systems). 

Vacuum metalizing is the process of coating a workpiece with metal by flash heating metal vapor in a high-vacuum chamber containing the workpiece. The vapor condenses on all exposed surfaces. 

Figure 2.5 Schematic representation of the gap of a metal-oxide-vacuum-metal tunneling junction in the case of a low (a) and a high (b) sample bias voltage.

Electroless deposition as we know it today has had many applications, e.g., in corrosion prevention [5-8], and electronics [9]. Although it yields a limited number of metals and alloys compared to electrodeposition, materials with unique properties, such as Ni-P (corrosion resistance) and Co-P (magnetic properties), are readily obtained by electroless deposition. It is in principle easier to obtain coatings of uniform thickness and composition using the electroless process, since one does not have the current density uniformity problem of electrodeposition. However, as we shall see, the practitioner of electroless deposition needs to be aware of the actions of solution additives and dissolved O2 gas on deposition kinetics, which affect deposit thickness and composition uniformity. Nevertheless, electroless deposition is experiencing increased interest in microelectronics, in part due to the need to replace expensive vacuum metallization methods with less expensive and selective deposition methods. The need to find creative deposition methods in the emerging field of nanofabrication is generating much interest in electroless deposition, at the present time more so as a useful process however, than as a subject of serious research. 

In ultralow (p < 10-7 torr) vacuum, metallic gaskets are used. 

The above results suggest a potential for utilizing surface fluorinated plastics for modified atmosphere and vacuum packaging applications. If needed, the barrier properties can be improved further by vacuum metalization. Excellent adhesion was found for vacuum-deposited aluminum on this new fluorinated layer, achieving an adhesion index of 10 using the classical cross-hatch method. With this treatment method it was also possible to heat-seal PP or PE onto PET. 

Re-usable containers, such as bottles for carbonated soft drinks, made of PEN have high-temperature tolerance for cleaning and sterilizing [79], The inherent UV resistance of PEN creates opportunities for colorless electronic and pharmaceutical packaging, as well as vacuum-metallized products for aerospace, industry and military applications [80, 81]. 

Metallized parts, vacuum metallized parts, reflectors. .. 

Decoration vacuum metallization gives good results. 

Decoration painting, vacuum metallization by vapour deposition, sputtering, plating, dichroic coating give good results. 

Decoration electroplating and vacuum metallization give good results. 

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

Samples suitable for SEM measurements include most solids which are stable under vacuum (metals, ceramics, polymers, minerals). Samples must be less than 2 cm in diameter. Non-conducting samples are usually coated with a thin layer of carbon or gold in order to prevent electrostatic charging. 

Fig. 1.4. A one-dimensional metal-vacuum-metal tunneling junction. The. sample, left, and the tip, right, are modeled as semi-infinite pieces of free-electron metal.

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