A Microelectrochemical Diode with Submicron Contact Spacing Based on the Connection of Two Microelectrodes Using Dissimilar Redox Polymers.
Interim technical rept.,
MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CHEMISTRY
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Closely spaced, 0.2-1 micrometer, Au microelectrodes on Si3N4 can be functionalized with polyvinylferrocene, PVFco, or with an N, N- dibenzyl-4,4-bipyridinium-based polymer, BPQ2n, derived from hydrolysis of N, N-bisP-trimethoxysilyl benzyl-4-4bipyridinium, I. Two- or eight-microelectrodes arrays can be connected with either polymer in the sense that net current can pass from one microelectrode to another, through the polymer, when one electrode is held at a potential where the polymer is oxidized and the other electrode is held at a potential where the polymer is reduced. From such steady state current an estimate of the diffusion coefficient for charge transport, DCT, in the polymer can be made values in the range .000000001- 10 to the --10 power sq cms are found and accord well with earlier measurements of DCT for te polymers studies. A two-terminal diode can be fabricated by coating one electrode with BPQ2n and an adjacent electrode with PVFco such that there is a connection between the microelectrodes via the BPQ2nPVFco contact. Current passes when the applied potential is such that negative lead is attached to the PVFc2n-coated electrode and the positive lead is attached to the PVFco-coated electrode. The switching time of a microelectrochemical diode is controlled by the time required to oxidize and reduce the polymers.
- Polymer Chemistry
- Electrical and Electronic Equipment