P n transition

For correct function of the ISFET, a sufficiently large gate voltage, Vq, must be applied between the leads to the reference electrode and to the substrate, so that a sufficiently large potential difference is formed between the surface and the interior of the substrate for formation of the n-type conductive channel at the insulator/substrate interface. This channel conductively connects drain 1 and source 2, which are connected with the substrate by a p-n transition. On application of voltage Vj between the drain and the source, drain current /p begins to pass. Under certain conditions the drain current is a linear function of the difference between Vq and the Volta potential difference between the substrate and the membrane. 

Maximum photosensitivity was obtained for two layer system containing a thin PVC-TNF layer covered by thick PVC layer [73] (Fig. 14). Here CT complex realizers photogeneration function and PVC the transport one. Memory effects, p-n transitions, and others may be obtained for multilayers and polydispersed systems. The photosensitivity of the last ones strongly depend from the incapsulation velocity of the inorganic photoconductors in polymer matrixes [79-81]. 

Table III. Results of the conductivity minima and Pq2 at p-n transition region.

Semiconductor p-n transitions with a band gap Eg are suitable for the detection of optical radiation, pro-... 

On contact between two different semiconductors both interfaces become charged. Well-known consequences are, for example, the thermo-electric effect for semiconductors, p-n transitions, and many other major issues in electronics . ... 

Pusey P N 1991 Colloidal suspensions Liquids, Freezing and Giass Transition ed J P Hansen, D Levesque and J Zinn-Justin (Amsterdam Elsevier) pp 763-942... 

These absorptions are ascribed to n-n transitions, that is, transitions of an electron from the highest occupied n molecular orbital (HOMO) to the lowest unoccupied n molecular orbital (LUMO). One can decide which orbitals are the HOMO and LUMO by filling electrons into the molecular energy level diagram from the bottom up, two electrons to each molecular orbital. The number of electrons is the number of sp carbon atoms contributing to the n system of a neuhal polyalkene, two for each double bond. In ethylene, there is only one occupied MO and one unoccupied MO. The occupied orbital in ethylene is p below the energy level represented by ot, and the unoccupied orbital is p above it. The separation between the only possibilities for the HOMO and LUMO is 2.00p. 

A further feature of the spectmm in Figure 9.24 is the sharp spike at the centre of each P-shaped transition. The reason for this is that saturation of the transition has occurred. This was discussed in Section 2.3.5.2 in the context of Lamb dips in microwave and millimetre wave spectroscopy and referred to the situation in which the two energy levels involved, m(lower) and n(upper), are close together. Under these circumstances saturation occurs when... 

P. N. Pusey, in D. Levesque, J.-P. Hansen, and J. Zinn-Justin, eds., Eiquids, Freeing and the Glass Transition, Les Houches Session LI, Elsevier, Amsterdam, The Nethedands, 1991, cited in Ref. 162. 

Heterometallic ferrocene-based transition metal compounds. P. N. Gaponik, A. I. Lesnitovich and Y. G. Orlik, Russ. Chem. Rev. (Engl. Transl), 1983,52,168-183 (293). 

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