Plated metal layer, scanning electron

Figure 7. Scanning electron micrographs showing rough morphology remaining on a polyimide surface after the plated metal layer is peeled off. Lower photo is a higher magnification of the area shown in upper photo.

If a heavy metal, e.g., Au, were preferentially plated out over the deformed region in the form of a thin layer, (e.g., in an electrochemical cell or simply by immersion in an appropriate solution, the resulting replica of the serial number could be made visible in the scanning electron microscope by elemental mapping of Au, where the location of the Au is displayed by analyzing for fluorescent Au X-radiation. This approach has yet to be examined experimentally. 

A cathode ray tube with a liquid crystal screen can be used as a transparency addressed by the electron beam [30, 48]. Here a necessary element is a vacuum-tight metal flber plate to form an electrical connection between the liquid crystal layer on the outside of the tube and the scanning electron beam. The resolving power of the device is determined by the spacing of the metallic wires and is about 10 lines mm (this figure can probably be... 

---