Fig. 3. Cross section of the SEM image of the specimen.
Fig. 4. EDS spectrum of the PEO coating.
Fig. 5. Id-Vd graphs of (a) the commercial n-MOSFET(2N7008) and (b) the EGFET with different pH values.
Fig. 1. (a) Schematic diagram of electrical measurement setup; (b) reference electrode, specimens, and corrosion-test cell.
Fig. 2. FE-SEM micrograph of the surface of the PEO coating. (a) 1k magnified image; (b) 30k magnified image.
Fig. 6. (a) pH versus Id in the saturated region; (b) linear regression of the relation between Id and pH from 4 to 12.
Table 1. Electrolyte composition
Table 2. EDS analysis of the PEO layer.
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