Electron beam evaporation , thin film sensors

The sensor shown in Figure 2 A was developed by stripping and cleaving F-MLD multimode fibers obtained from Newport Corporation with a 100 pm core and a 140 pm cladding diameter and then evaporating a very thin gold film (4-8 nm) on the fiber tips Electron-beam evaporation process was employed for carrying out the... 

For thin-film metallization, a thin metallic film is first deposited onto the surface of the substrate. The deposition can be accomplished by thermal evaporation, electronic-beam- or plasma-assisted sputtering, or ion-beam coating techniques, all standard microelectronic processes. A silicon wafer is the most commonly used substrate for thin-film sensor fabrication. Other substrate materials such as glass, quartz, and alumina can also be used. The adhesion of the thin metallic film to the substrate can be enhanced by using a selected metallic film. For example, the formation of gold film on silicon can be enhanced by first depositing a thin layer of chromium onto the substrate. This procedure is also a common practice in microelectronic processing. However, as noted above, this thin chromium layer may unintentionally participate in the electrode reaction. 

Durrani SMA, AI-Kuhaih ME Effect of biasing voltages and electrode metals and materials on the sensitivity of electron beam evaporated Hf02 thin film CO sensor. Mater. Chem. Phys. 2008 109(1) 56-60. DOI 10.1016/j. matchemphys.2007.10.034. 

Wisitsoraat, A.,Tuantranont, A.,Thanachayanont, C., Patthanasettakul, V. and Singjai, P. (2006) Electron beam evaporated carbon nanotube dispersed Sn02 thin film gas sensor , /. Electroceramics, 17,45-9. 

New techniques are being applied to develop miniaturized sensor arrays such as screen printing for thick film and electron beam evaporation, thermal vacuum deposition, and pulsed laser deposition for thin-film technique. Microfabrication techniques were used to prepare a sensor array for use in a voltammetric e-tongue by depositing gold (Au), platinum (Pt), iridium (Ir), and rhodium (Rh) on a silicon wafer. 

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