Characterization, wafer

Meyer, R, White, J. B., and Radle, M. (June 1999) Characterizing wafer contaminants. 

Extended defects range from well characterized dislocations to grain boundaries, interfaces, stacking faults, etch pits, D-defects, misfit dislocations (common in epitaxial growth), blisters induced by H or He implantation etc. Microscopic studies of such defects are very difficult, and crystal growers use years of experience and trial-and-error teclmiques to avoid or control them. Some extended defects can change in unpredictable ways upon heat treatments. Others become gettering centres for transition metals, a phenomenon which can be desirable or not, but is always difficult to control. Extended defects are sometimes cleverly used. For example, the smart-cut process relies on the controlled implantation of H followed by heat treatments to create blisters. This allows a thin layer of clean material to be lifted from a bulk wafer [261. 

Rejeb et al. described the development and characterization of immunoafflnity columns for the selective extraction of thifluzamide in peanuts. Efficient recovery was achieved using a simple elution profile requiring only 4 mL of methanol-wafer. De Jager and Andrews " described a novel fasf screening method for organochlorine... 

For these conditions, Armaou and Christofides [4] determine the thickness profile, in Fig. 10.4-3, for the amorphous silicon film after 60 s, when the average thickness reaches 500 A. When characterizing the non-uniformity of the film, the sharp increase in thickness calculated near the outer edge of the wafer is assumed to be due to the boundary conditions, which assume step changes to zero concentrations at the edge. Brass and Lee (2003) disregard the profile from r = 3.6 to 4 cm, and compute the non-uniformity as ... 

The nanowires in Fig. 10.5, straight and coiled, are believed to be SiNW. Experiments were performed to verify that they were not carbon nanotubes or metal nanorods. One method to prove this was by using a substrate other than Si. In this case, AI2O3 wafers replaced Si as the substrate to avoid interference from the Si substrate for characterization. The SiNW grown on Si are shown in Fig. 10.11, and those grown on the AI2O3 wafer are shown in Fig. 10.12. Characterization of these nanowires yielded that they were SiNW. 

Fairweather et al. [204] developed a microfluidic device and method to measure the capillary pressure as a function of fhe liquid water saturation for porous media wifh heferogeneous wetting properties during liquid and gas intrusions. In addition to being able to produce plots of capillary pressure as a function of liquid wafer safuration, their technique also allowed them to investigate both hydrophilic and hydrophobic pore volumes. This method is still in its early stages because the compression pressure and the temperatures were not controlled however, it can become a potential characterization technique that would permit further understanding of mass transport within the DL. 

Y. Huang, X.D. Chen, S. Fung, C.D. Beling and C.C. Ling, Spatial characterization of a 2 inch GaN wafer by Raman spectroscopy and capacitance-voltage measurements, J. Phys. D Appl. Phys., 37, 2814-2818 (2004). 

The wafers are processed into solar cells, the majority of which have a diode structure, as sketched in Figure 11.4, characterized by a thin, diffused, doped emitter, screen-printed front and back contacts and a front-surface antireflective coating. Prior to the effective cell manufacturing step, a chemical treatment of the silicon wafers removes... 

In many respects gold is more convenient than sihcon for characterizing polymer brush films. For instance, the RAIR spectra from planar gold are usually superior to that from sihcon wafers, especially for the SAM characterization. In addition, the S - Au bond is easily cleaved by treatment in a dilute solution of iodine. This allows for the isolation of the tethered polymer and the determination of Mn and PDI. The SAMs are easily deposited from dilute solutions of thiol or disulfide precursors. The only major disadvantage to gold is the instability of the weak S - Au bond, which is unstable above 60 °C, and imder UV irradiation in air. 

Experiments like those described above have been performed to evaluate sodium ion barrier properties of Hitachi PIQ and DuPont PI 2540 polyimide films. Also included in the comparison were silicon nitride coatings plasma deposited in both tensile and compressive stress modes. The structure of the samples is illustrated in Figure 9. N-type, (111) oriented silicon substrates were cleaned and oxidized in dry oxygen ambient at 1100°C to form a 1060 A Si02 film. Wafers intended for polyimide characterization were coated with an organic silane film (gamma glycidal amino propyl trimethoxysilane) to promote adhesion of the polyimide to the oxide surface. The polyimide resins were spun onto the wafers at speeds to produce final... 

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