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To provide a theoretical background for the superiority of the signal-domain phase-only correlation (SDPOC) technique proposed here for microdisplacement measurement, we study the first- and the second-order statistical properties of the complex amplitude of an analytic signal of a white-light speckle pattern, under the assumption of a Gaussian random process, and give a formula for the autocorrelation function of the pseudophase associated with the complex analytic signal. Based on these results, we show mathematically that SDPOC has a performance advantage over conventional intensity-based correlation techniques.

As an alternative to the intensity correlation used in conventional speckle metrology, we propose a new technique for displacement observation that is based on spatial-signal-domain phase-only correlation and that makes use of the pseudophase of the complex analytic signal generated from a Hilbert-filtered speckle pattern. Experimental results are presented that demonstrate the validity and the advantage of the proposed signal-domain phase-only correlation technique over both the conventional intensity correlation technique and the spatial-frequency-domain phase-only correlation technique.

Planar microwave discharges using a multislotted planar antenna are investigated. A three-dimensional finite-difference time-domain code is developed for the calculation of wave propagation in nonuniform plasmas. The enhancement of the microwave fields near the plasma resonance is revealed in accordance with the theory of the resonant absorption. The global wave electric field is obtained for various excitation modes of the antenna. By operating the antenna with transverse electric mode, where the field is rotating in the azimuthal direction, and by minimizing the reflected power from the antenna, highly uniform overdense plasmas can be produced in a wide range of gas pressures and microwave powers. Index Terms--Microwave discharge, plasma processing, resonant absorption, slot antenna.

CFx radical absolute densities in fluorocarbon plasmas were determined using single path infrared laser absorption and laser-induced fluorescence.

A quadrupole mass spectrometer is used to study the precursor species of fluorocarbon film growth at the reactor wall irradiated by an electron cyclotron resonance C4F8 plasma. The study shows that the fluxes of CFx radicals and positive ions incident upon the wall are shown to be comparable with the net condensed carbon flux derived from the growth rate and in contrast, the trends in the amount of polymeric neutrals are not well correlated to the growth rate.

The behavior of the densities of Si, SiF, and SiF[sub 2] radicals and SiF[sub 4] molecule were investigated for variations in electron density at pressure of 40 mTorr in a very high frequency (VHF) 60 MHz capacitively coupled plasma employing SiF[sub 4] gas. The SiF[sub 4] molecule was measured by infrared diode laser absorption spectroscopy, the SiF[sub 2] and SiF radicals were measured by laser-induced fluorescence, the Si atom was measured by ultraviolet absorption spectroscopy, and the F atom was measured by actinometric optical emission spectroscopy. The SiF[sub 4] density decreased with an increase in electron density, and the dissociation ratio of SiF[sub 4] was saturated to about 63% at electron densities of above 8.7 × 10[sup 10] cm[sup -3]. The SiF[sub 2] density decreased due to electron impact dissociation, whereas the F, Si, and SiF densities increased with an increase in electron density above 1.2 × 10[sup 11] cm[sup -3]. The total Si density was estimated to be of the order of 10[sup 10]- 10[sup 11] cm[sup -3]. Furthermore, the spatial distributions of SiF, SiF[sub 2], and SiF[sub 4] densities were investigated. They were almost flat inside the plasma region, but the SiF and SiF[sub 2] radicals decreased gradually outside the plasma region, and the SiF[sub 4] molecule increased. The behavior of the Si, SiF, and SiF[sub 2] radicals was in good agreement with the emission intensity of rare gases injected as trace gases. The kinetics of the species in VHF 60 MHz SiF[sub 4] plasma was clarified on the basis of the densities of the species and electrons measured. These experimental results are useful in predicting the radical densities of VHF SiF[sub 4] plasma using simulation. [ABSTRACT FROM AUTHOR]

The spatial distribution of the absolute density of CF[sub x] (x=1–3) radicals and their translational temperatures in an electron cyclotron resonance (ECR) plasma generated from a tetrafluorocarbon (C[sub 4]F[sub 8]) gas were examined using infrared diode-laser absorption spectroscopy (IRLAS) without a multiple reflection cell, namely, single-path IRLAS. Furthermore, we have developed a method of measuring CF and CF[sub 2] radical densities using single-path IRLAS combined with laser-induced fluorescence (LIF) spectroscopy. This method enables us to measure the spatial distribution of absolute radical densities with high accuracy, because of the IRLAS infrared laser beam and the LIF ultraviolet laser beam having identical paths. Under all the conditions studied, a spatially hollow distribution of the CF[sub 2] radical density is formed; the CF[sub 2] radical density in the vicinity of the chamber wall is much higher than that in the plasma. However, the spatial distribution of the CF radical density differs greatly from that of the CF[sub 2] radical density. The translational temperatures of CF and CF[sub 2] radicals are evaluated to be ∼700 K. On the basis of the measured results, we clarify the mechanisms of the formation of the spatial distribution, and conclude that the hollow distribution of the CF[sub 2] radical density is not caused by radical generation from the chamber wall, rather, the dominant mechanism for the formation of this distribution is the electron-impact dissociation of C[sub 4]F[sub 8] gas in the ECR region and diffusion from the upper part of the plasma chamber under the present plasma conditions where the flux of ions incident to the chamber wall is low. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The measurement of the absolute line-integrated density of the SiF4 molecule and the relative densities of SiF2 and SiF radicals as a function of Ne is studied. The SiF4 and SiF2 densities decreased while Si and SiF increased with an increase of Ne.

A novel feeding structure using a TE11 (transverse electric) rotating mode in a radial line slot antenna for plasma production is proposed. Moreover, novel slot patterns with different coupling slot distributions are fabricated and tested. Extremely uniform plasma over a large diameter is observed and the possibility of control of the plasma distribution in the radial direction by changing to different coupling slot distributions is verified. PACS No.: 52.40.Fd [ABSTRACT FROM AUTHOR]