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Accuracy is one of the most critical indicators of a machine tool’s value. The error induced in the manufacturing of a machine tool can account for as much as 75 % of the total part of the error formed under the use of that machine tool. Most of the components rejected due to out of tolerance are not the results of operator’s ignorance or material imperfection, but because of the distortions, wear, or initial inaccuracies of the machines. The precise basing, corrosion resistance, thermal conductivity, antifrictional and frictional properties, strength and rigidity, and many others as discussed in Chap. 5 collectively determine the final accuracy of the machine tool.

Non-destructive, on-line measurement and inspection of semiconductor products have become a very important process control function in the development and manufacturing of high density bipolar logic and memory array integrated circuit chips. Effective process control represents an essential factor in achieving higher yields, productivity and cost effectiveness in any manufacturing environment. One key way of achieving the process control objective is by integrating the collection, storage, analysis and display of measurement and inspection data at the work site. This approach helps the process engineer (1) better understand and identify the nature of an overall process problem or trend, (2) differentiate process from equipment performance problems, (3) implement corrective strategies traceable to problem sources, and (4) monitor and control process and tool critical parameters within upper and lower control limits from a mean target. Moreover, metrology and inspection functions are also important for determining process stability and establishing control baselines.

Foreword Preface Author's biographies Acknowledgments Introduction Manufacturing yield Problem diagnosis Manufacturing defect classification system Product dimensional metrology and pattern defect inspection Process and tool monitoring Contamination monitoring Repair and rework Test sites and vehicles for yield and process monitoring In-line electrical test Traceability Failure analysis of semiconductor devices Materials and chemical analysis of electronic devices Modeling for manufacturing diagnostics Artificial intelligence techniques for analysis: expert systems and neural networks Statistical quality control Reliability/defect severity Burn-in Defect prevention Index

The evolution of integrated circuit dimensions into the submicron region for the Very Large Scale Integration (VLSI) and Very High Speed Integrated Circuits (VHSIC) programs necessitates inspection techniques with a resolution exceeding that of the optical microscope. Inspection using scanning electron microscopes (SEM), operated in the low accelerating voltage mode, is becoming common place in the on-line fabrication of these submicron devices due to the high spatial resolution and greater depth of field afforded by these instruments. Use of the SEM is necessitated by the desire of many processing facilities which presently work at a 10% process control level to implement process control of 5% or better. This means that the process precision goal is now (or soon will be) in the nanometer range. Even though optical microscopes can be useful for critical linewidth measurement and inspection to about 0.5μm, many fabrication lines presently are integrating low-voltage scanning electron microscopes into the production sequence at chip levels of 1.25-μm geometry and below. This enables the training of operators and the acquisition and development of expertise and experience with control charts for this type of instrumentation. Advanced scanning e-beam instruments are presently being developed to facilitate this work and to do automated inspection.

The purpose of this short communication is twofold: (i) to support the reader with some basic knowledge about attempts to measure the Hausdorff dimension of space-time, and (ii) to cite some recent and useful literature for further in-depth study.