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A summary of the rapid high resolution full field ellipsometric imaging technique termed dynamic imaging microellipsometry is presented. The theoretical basis of a linear sensitivity coefficient approach to the coupling of individual error sources to ellipsometric absolute error is derived. Numerically computed sensitivity coefficient maps are presented with a discussion of their application to ellipsometric data calibration. An analysis of random error is presented and verified using comparisons between the theoretical estimations and system measurements.

A calibration method for interferometric systems is shown to produce a minimum wave amplitude to which these systems may be calibrated in the measurement of harmonic surface acoustic waves. The calibration limit is ~3 orders of magnitude larger than the theoretical detection limit. The method proposed allows experimental determination of the detection limit of these systems. The calibration of a fiber-optic heterodyne interferometer is demonstrated, and the experimentally derived detection limit for the interferometer is shown to be 5.5 × 10^−5 m for unity detection bandwidth. This limit is obtained for a mirrored specimen with 0.14 mW of laser power incident on the optical detector.

An optical correlation technique has been shown to accurately measure leak conduction rates from 10^−1 to 10^−6 atm cc/sec. Using hybrid microcircuit packages with glass capillary leakers, dimensional changes were detected as the packages were exposed to a small increase in external pressure. The rate at which the package returns to its original dimensions is measured and used, along with the internal free volume, to compute the leak rate. Because of its several advantages, the technique has the potential to become a useful nondestructive quality-control technique.

Using holographic matched filtering and electronic processing, small variations in surface displacement along the seam of a hermetic microcircuit package can be detected when the seam is stressed. Destructive analysis of a solder-sealed package reveals a strong correlation between optical signal variations and nonuniformity of solder adhesion and wetting along the seam. The technique promises potential application as a means of nondestructively inspecting for flaws in small welded or soldered seams.

The theoretical shot-noise-limited signal-to-noise ratio (SNR) is compared for one- and two-channel half-wave plate polarimeters, where rotation of the halfwave plate within the system causes a corresponding rotation in the incident linear polarization. This analysis estimates the smallest possible waveplate rotation that may be resolved by each polarimeter. It is shown that, at least theoretically, the differentially amplified two-channel polarimeter provides a superior SNR and thus correspondingly greater angular resolution. The degradation of the SNR as a result of polarization imperfections that might be introduced by less than ideal optical components is also considered.

Triple-exposure dual-reference beam holographic recording offers a convenient means by which high-speed transient phenomena may be investigated using heterodyne interferometry. Although convenient, use of the technique imposes certain compromises both in measurement linearity and sensitivity compared with analysis of more conventional double-exposure recordings. Fortunately, linearity can be assumed for events where only small (e.g., one-tenth wavelength) optical path changes are observed. By appropriate control of the intensity ratio of the reconstructed imagewave fronts, the region of linearity may be extended. Furthermore, measurement sensitivity can be optimized by proper control of recording and reconstruction parameters.

A triple-exposure recording technique has been developed which facilitates the recording of dual-reference beam holograms for heterodyne interferometry of high speed transient surface displacements. The technique overcomes many of the difficulties in recording double-exposure dual-reference beam holograms in a manner which satisfies the strict timing requirements usually associated with holographic recording of high speed phenomena. The technique has been applied successfully for recording and measuring displacements accompanying traveling surface acoustic waves.

Repetitively Q-switching a Nd:YAG laser during a single flashlamp pulse has been used successfully to generate a train of acoustic pulses with a repetition rate as high as 53 kHz. The spectral content of this multiple-pulse ultrasonic signal is significantly narrower in bandwidth than that of a single pulse. A corresponding reduction in the detection system bandwidth results in a marked improvement in detection sensitivity.

Dynamic imaging microellipsometry (DIM) is a new rapid full-field imaging technique for high spatial resolution studies of thin films. The DIM concept is based on radiometric polarizer, compensator, specimen, and analyzer ellipsometry combined with video and image processing techniques. The theoretical basis for this approach is developed using the Jones vector and matrix formalisms. Basic systems design is presented with error model predictions of ellipsometric accuracies better than 0.1° for full-field Δ and ψ images captured in a few seconds with spatial resolution under 10 μm. Initial feasibility tests have demonstrated interframe discriminations of 0.36° for Δ and 0.082° for ψ.