A STUDY ON ABSORPTION AND REFLECTION OF INFRARED LIGHT BY THE UNCOATED AND AL COATED SURFACES OF POLYMER FILMS TECHNIQUES - Polymers and Polymeric Composites - page 6

1.3.1.3 MORPHOLOGY OF MAGNETRON SPUTTERED FILMS

The polypropylene films were at 50-µm thickness and their one surface was
covered with 98-131 nm thick Al layer with magnetron sputtering [18]. In
Fig. 1.3, SEM micrographs of magnetron sputtered film are shown. In Fig.
1.3a, there is fractured Al coating on the surface of polypropylene. Figure
6 b. is the top view of the Al layer. From Fig. 1.3a, the coating thickness
is determined to be 185 nm, close to the value reported previously [18].
The top view of the Al layer seen in Fig. 1.3b indicated the surface was
covered by Al particles having nearly 30 nm size. The surface was not very
smooth. There are cracks on the surface of the brittle Al coating.

FIGURE 1.3 SEM pictures of (a) fractured Al coating on the cast polypropylene film; (b)
Al coated surface of the polypropylene film.

1.3.1.4 MORPHOLOGY OF MILK AND CHOCOLATE
PACKAGES

FIGURE 1.4 The photographs of (a) Chocolate packing (b) Milk cover.