Substrate planarization

Substrate planarization is a critical requirement in the fabrication technology of state-of-the-art integrated circuits (ICs). After a brief review of the existing planarization techniques the use of spin-on glass (SOG) films, which have the inherent quality of planarizing underlying topography, as an interlevel dielectric is described. The physical, chemical, and dielectric properties of two SOG materials,... 

Thus, substrate planarization has become an essential requirement In the fabrication technology of the state-of-the-art IC chips. 

In flexible displays employing metal foil substrate, planarization is required to reduce the surface roughness of metal foil and electrically insulate TFT array from conductive metal foil. Spin-on glass (SOG) and spin-on polymer (SOP) were selected as planarization dielectric. 2... 

Fig. 15 Schematic representation of the different types of supramolecular arrangements of discotics on surfaces with a edge-on orientation of the molecules, where the columnar axis is oriented parallel to the substrate (planar texture), and b face-on arrangement of the discotics leading to a homeotropic texture. Reproduced from [125]. (2005) Wiley-VCH...

LBL assembly also been extended to construct freestanding nanostructures by controllable assembling nanoparticles. Freely suspended flexible LBL structures with different shapes, compositions, and properties can be fabricated by using sacrificial substrates (planar, spherical, and cylindrical). Depending upon the fabrication procedure, freestanding LBL microcapsules, microtubules, microcubes, microcantilevers, and planar films can be obtained as shown in Fig. 8. 

Frequency noise spectra of a channeled substrate planar laser at room temperature operating at 10 raW and 17 mW single-ended output power. 

Planar microlens Distributed-index microlens with a three-dimensional index profile inside the planar substrate planar technology is applied to its construction and two-dimensional arrays can be formed by the photolithographic process. 

There are three main configurations for n nearby the surface of the substrate planar, homeotropic and tilted (Fig. 1.1). 

Ion-selective electrodes and amperometric ceUs have had a long history of success in a wide variety of appHcations (8,9). A microelectronics-inspired revolution is also occurring in these devices, brought about by the advent of photoHthographicaHy defined arrays of microelectrodes on planar substrates... 

Materials made of siHcon nitride, siHcon oxynitride, or sialon-bonded siHcon carbide have high thermal shock and corrosion resistance and may be used for pump parts, acid spray nozzles, and in aluminum reduction ceUs (156—159). A very porous siHcon carbide foam has been considered for surface combustion burner plates and filter media. It can also be used as a substrate carrying materials such as boron nitride as planar diffusion source for semiconductor doping appHcations. 

The most complete discussion of the electrophilic substitution in pyrazole, which experimentally always takes place at the 4-position in both the neutral pyrazole and the cation (Section 4.04.2.1.1), is to be found in (70JCS(B)1692). The results reported in Table 2 show that for (29), (30) and (31) both tt- and total (tt cr)-electron densities predict electrophilic substitution at the 4-position, with the exception of an older publication that should be considered no further (60AJC49). More elaborate models, within the CNDO approximation, have been used by Burton and Finar (70JCS(B)1692) to study the electrophilic substitution in (29) and (31). Considering the substrate plus the properties of the attacking species (H", Cl" ), they predict the correct orientation only for perpendicular attack on a planar site. For the neutral molecule (the cation is symmetrical) the second most reactive position towards H" and Cl" is the 5-position. The activation energies (kJmoF ) relative to the 4-position are H ", C-3, 28.3 C-5, 7.13 Cr, C-3, 34.4 C-5, 16.9. 

Often, Hertz s work [27] is presented in a very simple form as the solution to the problem of a compliant spherical indentor against a rigid planar substrate. The assumption of the modeling make it clear that this solution is the same as the model of a rigid sphere pressed against a compliant planar substrate. In these cases, the contact radius a is related to the radius of the indentor R, the modulus E, and the Poisson s ratio v of the non-rigid material, and the compressive load P by... 

Let us first consider the role of electrostatic forces. To do this, we will start with the simplest case of a spherical, uniformly charged, dielectric particle on a grounded, conducting planar substrate. 

Treating an asperity as an independent particle, JKR theory states that the force Ps needed to effect detachment of a spherical asperity from a planar substrate is given by... 

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