Stylus profilometer

The three-dimensional, quantitative nature of STM and SFM data permit in-depth statistical analysis of the surface that can include contributions from features 10 nm across or smaller. By contrast, optical and stylus profilometers average over areas a few hundred A across at best, and more typically a pm. Vertical resolution for SFM / STM is sub-A, better than that of other profilometers. STM and SFM are excellent high-resolution profilometers. 

STM and SFM are free from many of the artifacts that afflict other kinds of profilometers. Optical profilometers can experience complicated phase shifts when materials with different optical properties are encountered. The SFM is sensitive to topography oidy, independent of the optical properties of the surface. (STM may be sensitive to the optical properties of the material inasmuch as optical properties are related to electronic structure.) The tips of traditional stylus profilometers exert forces that can damage the surfaces of soft materials, whereas the force on SFM tips is many orders of magnitude lower. SFM can image even the tracks left by other stylus profilometers. 

Every material sputters at a characteristic rate, which can lead to significant amb ity in the presentation of depth profile measurements by sputtering. Before an accurate profile can be provided, the relative sputtering rates of the components of a material must be independently known and included, even though the total depth of the profile is normally determined (e.g., by stylus profilometer). To first order, SNMS offers a solution to this amb ity, since a measure of the total number of atoms being sputtered from the surface is provided by summing all RSF- and... 

The significance of instrument band width and modulation transfer function was discussed in connection with Equation (3) to characterize the roughness of nominally smooth surfaces. The mechanical (stylus) profilometer has a nonlinear response, and, strictly speaking, has no modulation transfer function because of this. The smallest spatial wavelength which the instrument can resolve, 4nin> given in terms of the stylus radius rand the amplitude aoi the structure as... 

R, D. Jacobson, S. R. Wilson, G. A. Al-Jumaily, J. R, McNeil, and J. M. Bennett. Microstructure Characterization by Angle-Resolved Scatter and Comparison to Measurements Made by Other Techniques. To be published in AppL Opt. This work discusses the band width and modulation transfer function of the scatterometer, stylus profilometer, optical pro-filometer, and total integrated scattering systems, and gives results of mea suring several surhices using all techniques. 

S. R, Wilson, G. A. Al-Jumaily, and J. R. McNeil. Nonlinear Characteristics of a Stylus Profilometer. Opt. Eng. 26,953, 1987. This describes modeling stylus profilometer response characteristics and explains their shortcomings. 

Surface roughness was measured according to ANSI standard 1346.1-(1978) using a Tencor Instruments Alpha-Step 200 stylus profilometer located at the National Nanofabrication Facility of Cornell. Five surface roughness measurements were made for each sample and their average values recorded. Details of the experimental apparatus set-up and its operation are given elsewhere (Dems, B. C. et. al. Inti. Polvm. Proc.. in press.). 

Surface Roughness measured with Tencor Instruments Alpha-Step 200 stylus profilometer per ANSI Standard 1346.1-(1978)... 

We first experimented with the Quartz Crystal Microbalance (QCM) in order to measure the ablation rate in 1987 (12). The only technique used before was the stylus profilometer which revealed enough accuracy for etch rate of the order of 0.1 pm, but was unable to probe the region of the ablation threshold where the etch rate is expressed in a few A/pulse. Polymer surfaces are easily damaged by the probe tip and the meaning of these measurements are often questionable. Scanning electron microscopy (21) and more recently interferometry (22) were also used. The principle of the QCM was demonstrated in 1957 by Sauerbrey (22) and the technique was developed in thin film chemistiy. analytical and physical chemistry (24). The equipment used in this work is described in previous publications (25). When connected to an appropriate oscillating circuit, the basic vibration frequency (FQ) of the crystal is 5 MHz. When a film covers one of the electrodes, a negative shift <5F, proportional to its mass, is induced ... 

Conceptually, predecessors of the scanning force microscope are the surface force apparatus (SFA) [73,74] and the stylus profilometer [75,76]. The SFA enables measurement of normal and friction forces between molecularly smooth surfaces as small as 1 nN as a function of distance with a resolution of 0.1 nm. In addition to the local force measurement, the profilometer provides a topographic map of the surface by scanning the surface with a sharp probe. However, the profilometer is not suitable for structure characterisation because of the large radius of the tip (about 1 pm) and the low sensitivity of the force sensor (in the range of 1(T2 to 1(T5 N). 

Figure S shows a schenutic of a long stylus profilometer trace. It is based on actual profilometry. The wafer has been polished so that the steps have been removed. Lower pattern density at the periphery of the dies has led to the formation of doming. The smaller humps are periodic with the same period as the die length. This periodic doming is superimposed on an overall wafer curvature. The wafer is not completely polished additional oxide could be removed.

Camera 2. Microscope 3. Objective lens 4. Stylus profilometer 5. Grinding wheel 6. Nozzle 7. Workpiece 8. Dynamometer 9. Spindle 10. Head 11. Motor 12. Cross roller guide 13. Position scale 14. Rotary encoder FIGURE 2.2... 

The Alq and TPD were deposited by thermal evaporation in a purpose built vacuum chamber at a pressure of approximately 10" mbar. Each material was placed in a glass crucible, which was heated to 180 "C for TPD and 220 °C in the case of Alq the corresponding deposition rates were 0.4 nm s for TPD and 0.1 nm s for Alq. The thickness of the films was measured by a Tencor Instruments Alpha-step 200 stylus profilometer 50 nm for TPD and 55 nm for Alq. 

Measured by four-probe method on 0.5-4 lm Ij-doped films cast from xylene. Films exposed to I2 for 4 h. Exact film thickness measured by stylus profilometer. 

Figure 13.2. Sink marks depth measured by stylus profilometer in two stage pressure molding of sheet molding compound vs. release time. [Adapted, by permission, from Dziewatkoski, N. A. Xu, J. Lee, L. J. Castro, J., Polym. Composites, 15, 2,106-17,1994.]...

Frictional characteristic of the UHMWPE-on-TZP sliding pair of current joint prostheses was also examined in this test for comparison. The TZP used in this test was the same material used in current ceramic joint prostheses and received hot isostatic pressing (HIP) treatment to reduce internal defects and improve the mechanical strength. The surface roughness of the HTOZ and TZP disk specimens measured by the stylus profilometer was 0.01pm (Ra). 

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