Optical Profiler

Optical Profiler Depth resolution Minimum step Maximum step Lateral resolution Maximum sample size Instrument cost... 

Figure 3 shows an optical profiler trace of the same portion of the wafer sample analyzed by the mechanical profiler. The resulting line scan in Figure 3a is similar to that for the mechanical system. The average and root-mean-square roughness are... 

Figure 3 Optical profiler measurements of a region on the unpolished back of a silicon wafer line scan (a) and 3D display (b) (Courtesy of WYCO Corp.).

As an example, consider again the back surface of the silicon wafer used in the mechanical profiler example. Eigure 4a, an SEM micrograph taken at 45° tilt, shows a surface covered with various sized square-shaped features that often overlap. This information cannot be discerned from the mechanical profiler trace, but can be obtained using a 3D optical profiler measurement. Eigures 4b and 4c are also... 

Some disadvantages for SEM measurements, compared with data from mechanical and optical profilers, are that the sample must be inserted into a vacuum system, and charging problems can make the analysis of insulators difficult. SEMs are also much more expensive than profilers. 

Figure 4. False-color optical profile images of ball wear surface for metal/metal contact...

NMR spectra were recorded using Bruker Biospin AV200 spectrometer (at 200 MHz for protons). Infrared spectra were recorded on a Bio-Rad FTS-40 attenuated total reflection Fourier transform IR (ATR-IR) using a horizontal ATR apparatus with a cadmium selenide crystal. Surface roughness was measured by an interferometerom-eter, which generates a 3D profile (Veeco WYKO NTllOO optical profiler). 

The partial trace in nuclear degrees of freedom in Eq. [13] is replaced in Eq. [18] by the constraint imposed on the collective reaction coordinate X representing the energy gap between the two levels involved in the transition. This reduces the many-body problem of calculating the activation dynamics in the coordinate space q to the dynamics over just one coordinate X. As we show in the discussion of optical transition below, the same Boltzmann factor as in Eq. [18] comes into expressions for optical profiles of CT bands. The solvent component of the FCWD then becomes... 

Compared with optical interferometric microscopes (optical profiles), it may provide unambiguous measurement of step heights, independent of reflectivity differences between materials. 

A non-contact laser surface profilometer which allows for precise characterization of surface profile has been purchased from Rodenstock Precision Optics. Profiles of microscopic surface terrain over spans of up to 60mm are achievable at a scan rate of 30 rnm/min. ITie laser beam allows surface height resolution on the order of one micron. In initial tests with the system, both longitudinal and radial profile scanning were successfully performed on cylindrical tensile test specimens. Radial scanning is possible because the footprint of the focused solid state laser (0.8 pm) is small compared to the radius of curvature of the specimen. 

Bhushan, B., Wyant, J.C. and Meiling, J. (1988) A new three-dimensional non-contact digital optical profiler. Wear,... 

A Wyko NT 1100 Optical Profiling System (Veeco, Philippines) was used to measure the surface roughness. The experiment was carried out in VSI mode using a 20x objective lens and a 0.5x field of view lens. The effective field of view was 0.62 mm x 0.47 mm. 5 spots on the surface were measured for each sample. The surface roughness was reported as root-mean-squared (rms) roughness calculated over the entire area measured. 

Photogenerated charge is usually introduced via excitons. Excitrais can be created at random positions within the film [9], or at random positions weighted by the expected optical profile within the device [15]. Excitons are typically assumed to move via Forster resonant energy transfer (FRET), which is described by the following equation [20] ... 

A Wyko NT2000 Optical Profiler and a JEOL JSM-5600LV Scanning Electron Microscope (SEM) were used to view and measure the molding inserts and also the polymer samples produced. For the samples, a carbon coating was applied to enable detection by the SEM. 

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