Hybrid device

Production scale. Although it can be a mass production technique, it is also adaptable to small batch production. The thick film process is therefore extremely useful in research where varying parameters may be tested on a small number of samples. Also, the eventual commercial market for such devices is probably not sufficient to warrant silicon IC fabrication on a massive scale. 

The lateral dimension of approximately 20 mm x 6 mm makes laboratory assembly and handling much easier than the ISFET analogue. 

Encapsulation. The larger scale of the device makes encapsulation for laboratory testing much simpler, and the processes involved are more easily carried out than the corresponding procedure required to encapsulate ISFET devices. 

It is important to emphasize that the thick film method of production is extremely versatile and adaptable to many experimental variations. Thin films may be interposed between thick film layers to experiment with back contact materials, and geometries can be altered as desired. Attempts to rationalize the various possible mechanisms and to construct thermodynamically reversible back contacts is made possible via this versatile technique. 

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Note The above switching devices by themselves or in conjunction w ith power diodes can be developed into a variety ol new devices to suit any power conversion and control application. MCTs and IGCTs arc a few such hybrid devices. For more details refer to the literature on the subject in the Further reading. 

In Section 13.2, we introduce the materials used in OLEDs. The most obvious classification of the organic materials used in OLEDs is small molecule versus polymer. This distinction relates more to the processing methods used than to the basic principles of operation of the final device. Small molecule materials are typically coated by thermal evaporation in vacuum, whereas polymers are usually spin-coated from solution. Vacuum evaporation lends itself to easy coaling of successive layers. With solution processing, one must consider the compatibility of each layer with the solvents used for coating subsequent layers. Increasingly, multilayered polymer devices arc being described in the literature and, naturally, hybrid devices with layers of both polymer and small molecule have been made. 

Figure 11.12. Si electrode and NW hybrid device, (a) Schematic of a single LED fabricated by the method outlined in Fig. 11.11. (b) I-V behavior for a crossed p-n junction formed between a fabricated p+-Si electrode and an n-CdS NW. (c) EL spectrum from the forward biased junction, (d) SEM image of a CdS NW assembled over seven p+-silicon electrodes on a SOI wafer (e) EL image recorded from an array consisting of a CdS NW crossing seven p+-Si electrodes. The image was acquired with +5V applied to each silicon electrode while the CdS NW was grounded. [Reprinted with permission from Ref. 59. Copyright 2005 Wiley-VCH Verlag.]...

A more recent paper considered the use of a hybrid power supply for powering autonomous microsen-sors. ° Such devices are similar to the dust mote pictured in Figure 1 and described in the Introduction. This hybrid power supply combined a solar cell to meet standby requirements and to charge the battery, which was the microfabricated Ni—Zn battery described in section 3.2. The authors also showed that if the battery alone was to serve as the power source, the footprint would be substantially larger, over 12 cm . The hybrid device was constructed and some feasibility experiments were carried out, but no actual devices were powered. 

Niemeyer, C. M. Functional hybrid devices of proteins and inorganic nanoparticles. Angew. Chem. Int. Ed. 42, 5796-5800 (2003). 

Dediu V, Hueso LE, Bergenti I, Riminucci A, Gorgatti F, Graziosi P, Newby C, Casoli F, de Jong MP, Taliani C, Zhan Y (2008) Room-temperature spintronics effects in Alq3-based hybrid devices. Phys Rev B 78 115203... 

Wash each filter with 100 mL of chloroform using the Screen-It colony hybridization device A single sheet of filter paper is used as an underfilter... 

Fu et al. [73] used a hybrid device for fabrication and packaging of microchips. This method consisted of a layer of inorganic substrate like silicon wafer and organic elastomer such as PDMS to perform multiple functions on an integrated chip. 

A hybrid device was constructed for DNA sequencing. Other than a micro-channel, a capillary tube was interfaced to a glass chip for separation [114]. 

Rhizon samplers are a hybrid device, which can be used in the laboratory, for example, pot experiments, as well as in the field (Cabrera, 1998 Knight et al., 1998). They represent one of the latest developments in terms of tension samplers, where it... 

Niemeyer et al. have reported the design of quantum dot/enzyme nanohybrids that are capable of catalyzing an organic transformation upon optical excitation of semiconductor quantum dots (QDs) [31]. The hybrid device was composed of semiconductor CdS nanoparticles and cytochrome p450BSp enzyme. It has been proposed that irradiation of QDs leads to formation of excitons (h+-e pairs) that on dissociation generate superoxide and hydroxyl radicals in interfacial electron transfer process (see Chapter 7). These radicals in turn activate the enzyme adsorbed at the QD surface. The activated enzyme is able to catalyze mono-oxygenation of fatty acids, but has a lower activity than the native enzyme [31]. 

Electrochemical detection was easily employed for the determination of uric acid in urine, abnormal concentrations of which have been linked to several disease states [14]. A glass/PDMS hybrid device with an off-chip platinum electrode was used to evaluate standard samples for both dopamine and uric acid. The linear responses for dopamine and uric acid were 1-165 and 15-110 pM, respectively, with a 1 pM limit of detection for both. Normal concentrations of uric acid in urine are 800-8000 pM, thus a 50 to 75-fold dilution was used with the urine samples analyzed to place them within the linear range of the detection method. Uric acid concentrations in these urine samples were confirmed using the clinically accepted method. This new method should allow clinical detection of both abnormally high and abnormally low uric acid concentrations in urine samples on a microdevice. 

In the field of biosensor technology, immobilized enzyme electrode development occupies a place of prominence due to the attractive performance of this hybrid device. Coupling an immobilized enzyme layer with an electrochemical sensor combines the advantages of using an insolubilized enzyme system (see below) with the sensitivity of readily available potentiometric and amperometric electrodes. The resulting biosensor enables direct, reliable, and reproducible... 

PLD of crystalline and stoichiometric ferroelectric materials has been successful for a number of materials. For example, crystaUine PbTiOs thin films have been deposited at only 350 °C using a KrF excimer laser (A. = 248 mn). The low deposition temperature makes this a potentially attractive method for directly fabricating ferroelectric/semiconductor hybrid devices. A related solid that is more difficult to prepare in thin film form is PbZri- ThOs. To maintain the Pb stoichiometry and ensure random mixing of Ti and Zr requires careful control of film synthesis conditions. ... 

The advantage of CVP, apart from the elimination of solvent induced contamination and oxidative defects, is that it is compatible with traditional inorganic semiconductor processes in the microelectronic and optoelectronic industry. This would be extremely important in the integration of polymer and inorganic semiconductors into hybrid devices with a minimum of processing steps. Moreover, CVP allows the mixture of monomeric compounds in any ratio, thus facilitating the deposition of graded films. 

The infusions of electrochemistry into the HTSC arena has been beneficial for the latter, and also fruitful for both fields. The role of electrochemistry has undeniably led to development of alternative methods for synthesizing HTSCs and their precursors, to methods of HTSC protection and modification of HTSC surfaces (including micro-and nanostructuring), to the fabrication of new hybrid devices that include the HTSC units, and also to new types of junctions. Highly sensitive, relatively simple, and reliable methods of the electrochemical analysis of both the volume and the surface of HTSC materials make it possible to quantitatively characterize the interaction of multicomponent oxides with the environment. In turn, electrochemical experimental methodologies have been enriched by new techniques for controlling the state of complicated and unusual objects under conditions unfamiliar to classical electrochemistry. 

Several polymer/polyelectrolyte-nanocrystal hybrid devices have been fabricated seeking to exploit the electro and photoluminescent properties of such material [179-188]. Device fabrication in all these cases is by low-cost self-assembly based techniques. These devices utilize thin films of these hybrids obtained either by multilayer deposition or drop/spin casting methods. Thus, solar cells have been made from poly(2-hexylthiophene)-CdSe nanorod multilayers, lasers from drop cast films of CdSe-titania composites and an infrared emitter from multilayers... 

Step 9a New intensified microstructured devices Step 9b New intensified hybrid devices Step 9c New intensified Mesoscale process units ... 

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