Wafer surface evolution

Chekina (Chekina et al., 1998) proposed a physical model to calculate feature topography evolution. The pad elastic deformation and the wafer surface evolution are considered on the basis of contact mechanics and the theory of wear contact problems. 

Budding on the general wafer removal models of the previous section, this section considers models related to how wafer surface material is planarized. These include models for feature-level evolution, and die-level models for planarization as functions of layout, pad, and asperity properties. Again, our goal is not to provide a comprehensive survey of existing CMP models instead, our purpose is to present models that demonstrate how key physical effects in planarization can be predicted. 

Intensity-modulated photocurrent spectroscopy has been used in combination with microwave reflectivity measurements to investigate hydrogen evolution at a p-type silicon45 and an n-type silicon.46 The measurement of amplitude and phase under harmonic generation of excess carriers, performed by Otaredian47 on silicon wafers in an attempt to separate bulk and surface recombination, should also be mentioned here. 

The year 2000 will mark 15 years since the initial CMP patents were filed by IBM. Opportunities for expanding use of CMP in existing chip technology continue to flourish. In addition, the challenges ahead for CMP technology to keep pace are formidable in this third wave of the evolution of the technology. Increasing concern about improved within-wafer nonuniformity, better planarity (flatter surfaces), and lower defectivity levels are all requirements for advanced, sub-0.25-micron devices. In addition. 

Figures 4(a-c) show three ESCA Si 2p spectra resulting from the (a) Y58 blank, (b) HMDS (SVG track) and (c) HMDS ( 2000)/Y58 wafer, respectively All spectra were recorded at 5 take-off angle These spectra clearly indicate the evolution of a new peak between the elemental silicon and the SiO peaks The growth is very pronounced in the case of the HMDS ( 2000)/Y58 treated wafer The new Si 2p peak, arising from HMDS treatment of the wafer, is centered at 101 8 eV (see Figures 4b and 4c) The other five peaks present in the spectrum of the blank wafer are assigned to Si, SiO, Si O and SiO species (4) The new peak at 101 8 eV is assigned to (cHp Si-0-type of Si species formed on the surface due to the HMDS reaction.

As discussed earlier, it is now possible to make and study deposits of monosized, highly dispersed, transition metal clusters.(S) In this section we summarize results from the first measurements of the valence and core level photoemission spectra of mass selected, monodispersed platinum clusters. The samples are prepared by depositing single size clusters either on amorphous carbon or upon the natural silica layer of a silicon wafer. We allow the deposition to proceed until about 10 per cent of the surface in a 0.25 cm2 area is covered. For samples consisting of the platinum atom through the six atom duster, we have measured the evolution of the individual valence band electronic structure and the Pt 4f... 

In this paper we describe a model of a cup plater with a peripheral continuous contact and passive elements that shape the potential field. The model takes into account the ohmic drop in the electrolyte, the charge-transfer overpotential at the electrode surface, the ohmic drop within the seed layer, and the transient effect of the growing metal film as it plates up (treated as a series of pseudo-steady time steps). Comparison of experimental plated thickness profiles with thickness profile evolution predicted by the model is shown. Tool scale-up for 300 mm wafers was also simulated and compared with results from a dimensionless analysis. 

Wafer Bonding, Fig. 1 Evolution of surface energy with temperature for hydrophobic and hydrophilic surfaces... 

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