Semiconducting substrates

Figure 4.2 Schematic diagram of a charge-coupled device (CCD) imaging sensor. It consists of a semiconducting substrate (silicon), topped by a conducting material (doped polysilicon), separated by an insulating layer of silicon dioxide. By applying charge to the polysilicon electrodes, a localized potential well is formed, which traps the charge created by the incident light as it enters the silicon substrate.

Dopant. Dopant species may be introduced into the semiconducting substrate at various points in the process and by different means. As mentioned above, some dopant may be added to the molten solution as the single crystal is being grown. Dopant introduced in subsequent steps (see steps 1, 3, 4, and 5, Table I) may be introduced by means of diffusion or ion implantation. 

It is to note that some of the issues touched upon in this chapter still require a more detailed experimental study and theoretical interpretation. In particular, the model considered above, which makes it possible to relate an increase in the catalytic activity to appearance of charge on nanoparticles, undoubtedly needs refinement and a more thorough experimental verification. A clear understanding of the important issue of how the electrical properties of conducting supports affect the catalytic activity of deposited structures requires that, in the first place, experiments with a larger number of reactions and a wide variety of metallic and semiconducting substrates... 

Kunitsyn AE, Kozyrev SV, Novikov SV, Savel ev IG, Chaldyshev VV, Sharonova LV (1994) Production of Fullerene Films on GaAs Semiconducting Substrates, Phys Solid State 36 2573-2579... 

Again, photoelectron emission of semiconducting substrates can take place in metal nucleation. In addition, a complementary photoeffect, the photoemission of excited holes and oxidative decomposition of water, has to be considered in analogy to n-type semiconductors. 

The recent development of high T superconductors opens a whole new realm of possible chemistry involving supercondcting solids and surfaces. It had always been assumed that a perfect conductor did not exist, but now comes a special kind of perfect conductor available at temperatures readily accessible to chemists. An example of new chemistry is laser-induced chemical vapor deposition, where a laser could be used to "write" an insulating layer or a "normal" conducting layer on top of a superconductor, or even to write a superconductor on a semiconducting substrate. 

It is our purpose in this work to present some interesting results obtained by electrodepositing thin layers of Cu, Co and Ni directly onto Si substrates, i.e., without the presence of a seed layer. As it is well known, semiconducting substrates can conduct sufficiently well to allow direct electrodeposition. Different groups have already... 

A recent variant of the rotating disc OMVPE reactor utilizes a water-cooled closespaced reactant injector. This technology shown in Figure 4-17, was principally developed by Rome Air Force Laboratory (U.S. patent 5 129360). In a conventional RDR OMVPE reactor, the injector through which the gaseous reactants flow is placed = 75-150 mm from the hot (600-700 °C) semiconducting substrate to insure that the... 

Numerous attempts were made to improve the adhesion of poly(vinyl cinna-mate) resist on the semiconducting substrates, but it soon became apparent that a new-materials approach was needed in order to satisfactorily resolve this problem. ... 

A method for enhancing adhesion of resist materials onto surfaces of silicon dioxide and other semiconducting substrates was invented by Collins and Deverse, and involves subjecting the surface to an atmosphere containing the... 

Dry etching is the primary etching method currently used to transfer the resist pattern into underlying semiconducting substrates in an IC device. The pattern transfer is accomplished by removing underlying substrate materials that are not... 

Masks and reticles contain the blueprints or the patterns of the circuit elements used as templates in the fabrication of IC devices. They provide the templates of the circuit elements from which numerous replications, perhaps numbering in the millions, are made. The object of lithography is to transfer these blueprints to semiconducting substrates such as silicon wafers. 

IR absorption in the presence of composite films In Section 6.4, we noticed that the presence of a thin film over the semiconductor surface may lead to a decreased IR absorption from the electrolyte in ATR geometry. A quantitative analysis of this effect requires going beyond the treatment leading to Eqs. (l)-(2), which did not take absorption of medium 2 into account. The result actually depends on the refractive index of the film. If it is lower than that of the semiconducting substrate Ui, a loss in electrolyte absorption is indeed to be expected (most frequent case for an oxide film). If it is equal or close to Uj, total reflection takes place at the outer edge of the film, and no change in electrolyte absorption is to be expected. 

Applied to materials where the understanding of the electronic structure of the surface is poor such as molecular films on metallic or semiconducting substrates. 

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