Silicon surface image

Figure 14.26 Semispherical droplets of Alq3. AFM images of printed samples replicating a squared grid. Deposition of an Alq3 solution on a hydrophobic silicon surface (image taken from Ref. 105).

Fig. 35. Process flow for thin-film imaging lithography (a) bilayer process and (b) top surface imaging. The bilayer process shown here employs a positive-tone imaging layer. The TSI process illustrated refles on preferential silicon incorporation in the exposed regions of the imaging layer to give a...

Gold nanoparticles can be clearly observed as white dots and silicon wafers are black in HR-SEM images of the gold nanoparticles-immobilized silicon surface. When immobilizing the allylthiol (C3, HS-CHj-CH = CHj)-stabilized gold nanoparticles, even the reaction temperature was as low as 50 °C, the white dots with diameters about lO Onm are observed (Figure 5A). 

Figure 5.7 AFM images of fibrous aggregates of D-Glu-8 (1) lying directly on silicon surfaces (a) network of fibers (b) high-resolution phase image of quadruple helices. Reprinted with permission from Ref. 42. Copyright 2000 by the American Chemical Society.

Fig. 25 AFM images of silicon chip siufaces a cleaned, rehydroxylated silicon surface, b self-assembled MPTS layer on silicon, c immobilised oligonucleotide probe, d surface after hybridisation to a complementary target [119]. Reprinted with permission...

To understand the meaning of the STM images of silicon surfaces, we review some basic facts of the crystallography of silicon. We will discuss the simpler Si(lll) surfaces first, then the complicated 7X7 reconstruction. In fact, the STM imaging of the simple Si(lll) surface is the most elementary case of imaging semiconductors, and perhaps the most instructive one. 

Fig. 4.15 (a) A 15 K He field ion image of a low temperature field evaporated silicon surface. (b) A computer simulation image of Si with (lxl) surfaces, (c) a 60 K Ne field ion image of a 720°C annealed silicon surface where well ordered atomic structures are developed at a few facets of the Si emitter surface, (d) When the Si tip is annealed at 800°C, almost all the facets are well developed. The atomic structures of all these facets are completely reconstructed. 

Figure 5.14. STM images of the well-ordered monolayers formed from the reaction of (a) cyclopentene and (b) 1,5-cyclooctadiene with Si(100)—2 x 1. The images in (a) are collected on a vicinal silicon surface, as described in the text, (i) and (ii) are before and after saturation exposure to cyclopentene, respectively. The images in (b) include (i) the 1,5-cyclooctadiene molecule, (ii) and (in) STM images of saturation coverge of 1,5-cyclooctadiene, and (iv) a model of the molecule bonded across a Si-Si dimer. Both molecules form well-ordered monolayers on Si(100)-2x 1. Figure adapted from Ref. [218] with kind permission of Springer Science and Business Media.

Fig. 4. Magnified millions of times are surface atoms of silicon. The image is computer-generated from data produced by a scanning tunneling microscope. (IBM Corporation)...

FIGURE 2.7. AFM image of PS matrix after removing PMMA columns on neutralized silicon surface with a total film thickness of 42 nm. The insert shows the centre-to-centre distance d and the distance D required to fit two rows of PMMA columns (42 nm and 72 nm respectively). 

Some of the most dramatic STM images have been recorded for the Si(l 11) 7X7 reconstruction, as depicted in Figure 3.14.138 These images have been recorded at several different biases (see Spectroscopy and Chemical Selectivity, below) and provide one of the best examples of how STM can be used to better understand the chemistry of such surfaces ( specifically, the electrophilicity and nucleophilicity of the individual surface atoms). Clearly depicted in these results are the orbitals associated with surface atoms, rest atoms, and backbonds. Such studies have continued and been greatly extended into the exploration of a variety of chemical reactions that occur on silicon surfaces. These studies are described in detail in a recent review.135... 

The imager of JP-A-6089991 (Toshiba Corp., Japan, 29.03.94) comprises HgCdTe detector regions which have been grown on a silicon substrate. A method to clean the silicon surface before the HgCdTe regions are grown thereon is disclosed. 

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