Monocrystalline silicon

The single-crystalline wafers are classified according to the crystalline orientation of the surfaces based on the Miller indices. Miller indices are referenced with respect to the crystallographic axes of a crystal and therefore do not have to be oriented at right angles. However, they correspond to the x-, y-, and z-axis of a cubic lattice structure. 

Determine the points at which a given crystal plane intersects the three axis, say, (a, 0,0), (0, b, 0), and (0,0, c). If the plane is parallel to an axes, it is said to intersect at infinity. 

The Miller index for the face is ( where the three numbers are expressed as smallest integers, that is, common factors are removed. 

Silicon is produced by a well-controlled Czochralski crystal growth process in a very clean environment, that is, class of 1 or 10. In this process, a small seed crystal is dipped into a highly purified silicon melt. This seed is slowly pulled while the crucible containing the melt is rotated. The silicon crystal grows along the selected orientation of the seed to the rod. A cylindrical crystal is obtained from which slices are cut. This is followed by the atomic polishing phase. The side of one cubic face is 5.43A. The mechanical, electrical, and thermal properties of silicon have been presented in Table 10.1. 

Miller index for Yonng s modnlns Shear modulus 

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Sugimoto Y, Peter LM (1995) Cathodic electrodeposition of CdTe on n-type monocrystalline silicon. J Electroanal Chem 381 251-255... 

Gangopadhyay et al.48 used a CBD ZnS antireflection coating on large-area commercial monocrystalline silicon solar cells, resulting in a 13.8% efficiency. Ennaoui et al.49 deposited CBD Zn(Se,OH)x films on Cu(In,Ga)(S,Se)2. They reported an active-area efficiency of up to 15.7% and a total-area efficiency of up to 13.26% for such devices. 

The satellite would need 50 to 100 square kilometers of collector area using 14% efficient monocrystalline silicon solar cells. More expensive triple junction gallium arsenide solar cells with an efficiency of 28% would reduce the collector area by half. In both cases the solar station s structure would be several kilometers wide, making it much larger than most manmade structures on Earth. Building structures of this size in orbit has never been attempted before. 

Fig. 10.3 Colour contrast of human erythrocytes on different solid reflective substrates Al -polycrystalline aluminum Cu - polycrystalline copper Mo - monocrystalline molybdenum Ni - polycrystalline nickel Pt - chemically polished platinum Si(m) - monocrystalline silicon Si(p) - polycrystalline silicon Ti - chemically polished titanium W- monocrystalline tungsten...

Wet chemical anisotropic etching of monocrystalline silicon has been widely applied in microtechnology (18,20). This method is based on the dependence of etching velocity on crystal orientation, so only a few basic geometries can be... 

The flexible solar module based on monocrystalline silicon cells with higher efficiency than thin film solar cells was developed in the VIESH. For example, the folding solar module 36/1-6-P depicted at FigurelO supplies 10W, output voltage 16V, and short circuit current, 0.7A under standard conditions of measurements. His dimensions are 395 x 370 x 4 mm and in the folded condition practically 6 times less by surface (135 x 185 x 12 mm). This folding solar module can be used for applications which small consuming equipment. 

Manz, A., Fettinger, J.C., Verpoorte, E., Liidi, H., Widmer, H.M., Harrison, D.J., Micromachining of monocrystalline silicon and glass for chemical analysis systems. Trends. Anal. Chem. 1991, 10, 144—149. 

An analogous mask 4, with a complementary geometry with respect to that on the chip 1, is applied to a slice of monocrystalline silicon. The substrate is chemically etched to form a recess... 

Chemical products used today in electronics seem, at first glance, to be a very ordinary kind. They are different from those generally offered, however, by reason of the extraordinary degree of purity which their producers must achieve in order to satisfy the stringent requirements of the electronics industry. The maximum dose of impurities tolerated in monocrystalline silicon amounts to one part in 1013. 

Polycrystalline silicon, produced from silane (SiH4) or trichlorosilane (SiHCl3) forms the upstream part of the semiconductor sector. Monocrystalline silicon is extracted from polycrystalline silicon and sliced into wafers 25 microns thick and 8 to 10 centimeters in diameter. 

SIMOX [Separation by IMplanted OXygen] In the manufacture of semiconductor devices, a thin layer of insulating silicon dioxide is formed beneath the surface of a monocrystalline silicon substrate to form a buried dielectric layer. The layer is formed by implanting oxygen ions at 500 to 600°C and then annealing at > 1000°C. 

It is noted that the polishing of the polysilicon film will employ the well-known technology of polishing monocrystalline silicon substrates. This gives an opportunity to examine the effect of polycrystallinity and thus of grain boundaries and grain orientation in CMP of Si. Doped vs. undoped polysilicon will also shed... 

Fig. 1 presents the EELS data for silicon growth (Vsi=0.17 nm/min at substrate temperature 150°C) atop 2D Mg2Si with structure (2/3)V3-R30°. It is apparent, that surface phase does not destroy at Si overgrowth and 2 nm of Si completely cover the silicide phase. However, the surface plasmon shifted to lower energy at 20 nm of Si thickness, while position of bulk plasmon corresponded to the monocrystalline silicon. The main cause of the given difference is the strong surface relief Therefore in this case the known relation between bulk and surface plasmons for atomically clean surface is not valid. 

The determination of the true specific surface area of the Pt electrode is possible with the analysis of the hydrogen anodic region of the potentiodynamic curve [7]. It amounts to 80 a.u. for macroporous electrode and 840 a.u. for mesoporous one in comparison to the surface of monocrystalline silicon. 

F.Gao, G. Zhu, X. Li, B. Li, S. Qiu, and O. Terasaki, Synthesis of a High-quality Host Material Zeolite MFI Giant Single Crystal from Monocrystalline Silicon Slice. J. Phys. Chem. B 2001, 105, 12704-12708. 

In the 1990 race the winning car used monocrystalline silicon cells of the advanced, laser-grooved buried-grid type. The 1993 winner was powered by 20% efficient monocrystalline silicon PV cells, which achieved an average speed of 85-km per hour over the 300-km course. 

One of the most important issues for simulation of microsystems is to know the properties of the materials. In the case of microcantilevers, young modulus, Poisson s ratio, and density are the main parameters to be considered. If monocrystalline silicon is used, as reported in this work, the mechanical properties are well-known (see Table 1). For an anisotropic material such as silicon, the Young s modulus, Poisson s ratio, and shear modulus depend on which crystal direction the material is being stretched. The appropriate values for each direction have to be introduced in the model. 

The structural materials that conform the cantilevers can have intrinsic stresses and stress gradients because of the fabrication processes. These can change the mechanical performance of the microcantilevers. If stresses and stress gradients are high, they must be previously measured by using specific test structures and their values should be included in the simulations. As monocrystalline silicon will be used in the fabrication of our devices, these stresses can be neglected. 

Tb-implanted thermally grown silicon dioxide film, and (iii) Tb-doped alumina xerogels fabricated onto monocrystalline silicon. Thus, the terbium-doped alumina xerogel/PAA structure was proposed as a basis for green room-temperature luminescent images [17]. 

Figure 4. Indicatrices of PL from the sfructure titania xerogel/PAA of 30 gm thick ( ) and from the same xerogel on monocrystalline silicon (A).

Monocrystalline silicon samples (10x 10x0.28mm ) of (HI) and (100) crystallographic orientations were mounted at an axis of the system normally to compression flow at distances of 6-16 cm from the tip of MFC discharge device. The surface microrelief of the silicon samples was examined with high-resolution scamiing electron microscopy (SEM). 

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