Gate electrode

Fig. 4. (a) TEM image of TaN metal electrode gate stack after Ch etching, revealing thick residues formation on the sidewall (etching was done in DPS) SEM image of TaN metal electrode (b) before and (c) after DHF cleaning. 

This class of CCD has a higher quantum yield than a front-illuminated similar CCD. The origin of this improvement is as follows. The silicon substrate for the chip is etched down, on the face opposite the electrodes, to reach a thin layer (—15 pm), and the light illuminates the array from the back, opposite from the usual way (Fig. 4). It was noted in Sec. 5 that electrode gates that are used for the readout process overlap the pixel surface. Since these electrodes have a given thickness and are laid on the front face, photoelectrons have to travel across a... 

STM measurements on molecular junctions in solution have been realized by groups in Miami [66], Lyngby [34] and Liverpool [33, 67]. Performing the STM experiments in a liquid environment provides a way to combine well-established electrochemical techniques with in situ electronic STM characterization of a single or a small number of molecules. One particular advantage of this approach is the option to use an electrochemical reference electrode as a third electrode (gate) in the setup in addition to the tip and substrate electrodes (source and drain). Such a setup closely resembles a (three-terminal) transistor setup, as the third electrode can be used to manipulate the transmission properties of the junction molecules by applying a potential between the substrate and the reference electrode. 

Year Mobility [cm2V ls l] Material (deposition method) — V x IV] Ion/ off Source-drain electrode Gate electrode Insulator Reference... 

Figure 2.2 Schematic of in situ STM. In this four-electrode configuration the working electrode potential is controlled relative to the electrochemical reference electrode ( gate ) and the (coated) tip potential relative to the...

Since the ISFET is based on the field-effect transistor, let us recall briefly how the latter operates (see, e.g.. Ref. 98). The field-effect transistor (Fig. 19a) represents the so-called MIS (metal-insulator-semiconductor) structure (hence the abbreviation MIS-FET), i.e., a semiconductor base, onto which an insulating layer and a metal electrode (gate) are deposited. The base usually is a p-type silicon plate and the insulator, a Si02 or Si3N4 layer. With a thickness of 100-200 nm, the resistance of this layer is of the order of 10 fl. Two regions are produced in the base by local... 

Instead of floating nanoelectrodes (CNTs), our laboratory [3-7] is able to fabricate 50 nm nanoslots on glass (inset in Fig. 3b) and is able to show concentration of ssDNA to the nanoslot. The same DNA concentration is shown with nanoporous membranes in Fig. 3, with a concentration factor of up to five orders of magnitude. Alternatively, 100 nm nanocolloids can be assembled into a nanocolloid crystal (a membrane) at a top-down electrode pair by nanocolloid DEP (Figs. Ic, 6). The 10 nm spacing between the nanocolloids focuses the electric field of the electrode gate and can rapidly (order of seconds) trap and concentrate ssDNA... 

Fig. 6.2. The basic MIS CCD structure illustrating charge transfer with three-phase dock voltage operation. In silicon devices overlapping polysilicon electrode gates are often used...

Field effect transistors In the fabrication of some potentiometric and gas-sensitive biochemical sensors an important role is played by unipolar transistors controlled by an electrical field (field effect transistors, FET) with a conducting channel isolated from the control electrode (gate) by a thin layer of insulator (MISFET-metal insulated semiconductor FET) made of Si02 (MOSFET-metal oxide semicon-... 

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