Abstract: Mass-transfer rate control arrangement and method in which a process precursor mixture is produced containing carrier gas and a process precursor gas. A quantity of the process precursor present in the process precursor mixture is acoustically sensed to produce a sensor output. A dilution gas is provided and the process precursor mixture and the dilution gas are separately conveyed to a dilution point, at which a diluted mixture of the dilution gas and the process precursor mixture is achieved. A relative flow rate of the carrier gas and the dilution gas is automatically controlled in response to the sensor output such that the diluted mixture at the dilution point has a prescribed mass transfer rate of the precursor gas.

Abstract: Mass-transfer rate control arrangement and method in which a process precursor mixture is produced containing carrier gas and a process precursor gas. A quantity of the process precursor present in the process precursor mixture is acoustically sensed to produce a sensor output. A dilution gas is provided and the process precursor mixture and the dilution gas are separately conveyed to a diution point, at which a diluted mixture of the dilution gas and the process precursor mixture is achieved. A relative flow rate of the carrier gas and the dilution gas is automatically controlled in response to the sensor output such that the diluted mixture at the dilution point has a prescribed mass transfer rate of the precursor gas.

Abstract: An optical system includes both a microspot broadband spectroscopic ellipsometer and a photoacoustic film thickness measurement system that are supplied laser light by the same laser light source. One of the systems makes a measurement, the result of which is used to adjust a parameter of the other system; e.g. the ellipsometer measures thickness and the photoacoustic system uses the thickness result to measure the speed of sound. In one version, the ellipsometer converts the laser beam to a broad-spectrum beam that provides higher intensity.

Abstract: An optical system includes both a microspot broadband spectroscopic ellipsometer and a photoacoustic film thickness measurement system that are supplied laser light by the same laser light source. One of the systems makes a measurement, the result of which is used to adjust a parameter of the other system; e.g. the ellipsometer measures thickness and the photoacoustic system uses the thickness result to measure the speed of sound. In one version, the ellipsometer converts the laser beam to a broad-spectrum beam that provides higher intensity.

Abstract: An optical system includes both a microspot broadband spectroscopic ellipsometer and a photoacoustic film thickness measurement system that are supplied laser light by the same laser light source. One of the systems makes a measurement, the result of which is used to adjust a parameter of the other system; e.g. the ellipsometer measures thickness and the photoacoustic system uses the thickness result to measure the speed of sound. In one version, the ellipsometer converts the laser beam to a broad-spectrum beam that provides higher intensity.

Abstract: An optical system includes both a microspot broadband spectroscopic ellipsometer and a photoacoustic film thickness measurement system that are supplied laser light by the same laser light source. One of the systems makes a measurement, the result of which is used to adjust a parameter of the other system; e.g. the ellipsometer measures thickness and the photoacoustic system uses the thickness result to measure the speed of sound. In one version, the ellipsometer converts the laser beam to a broad-spectrum beam that provides higher intensity.

Abstract: A photoacoustic system with ellipsometer, where the ellipsometer includes a laser light source for generating an incident beam, an element for focusing the incident beam on a sample, a unit for measuring the change in amplitude of the incident beam on reflection and a unit for measuring the phase difference of the incident beam on reflection. The system further includes an element to convert an input narrow spectrum beam generated by the laser light source to a broadband sample measurement beam that is focused onto the sample.

Abstract: A system comprising a means for generating an optical pump beam pulse and for directing the optical pump beam pulse to a first area of a surface of a sample having a plurality of film layers to generate an acoustic signal, a means for generating an x-ray probe pulse and for directing the x-ray probe pulse to a second area of the surface, a means for detecting an intensity of a diffracted x-ray probe pulse the intensity varying in response to the acoustic signal to form a probe pulse response signal, and a means for calculating an expected transient response to a theoretical acoustic signal propagated through a model of the sample and fitting the probe pulse response to the transient response to derive at least one characteristic of the sample.

Abstract: A photoacoustic system with ellipsometer, where the ellipsometer includes a laser light source for generating an incident beam, an element for focusing the incident beam on a sample, a unit for measuring the change in amplitude of the incident beam on reflection and a unit for measuring the phase difference of the incident beam on reflection. The system further includes an element to convert an input narrow spectrum beam generated by the laser light source to a broadband sample measurement beam that is focused onto the sample.

Abstract: An apparatus for improving the signal to noise ratio of measurements of the thickness of layers in a thin film stack uses a photoacoustic measurement system that includes a time differentiation system for inducing a delay in pump beam pulses. The time differentiation system uses, among other things, a birefringent element and other elements to control the polarization of pump beam pulses. Use of the apparatus involves applying a time varying voltage to an electro-optic modulator driver and setting a time differentiation step; or, in another embodiment, applying a time varying voltage to an electro-optic modulator to induce a fixed time delay delta-t between a vertically polarized pulse and a horizontally polarized pulse. The high frequency operation of the system provides for improved determinations of film thickness.

Abstract: An optical metrology system is provided with a data analysis method to determine the elastic moduli of optically transparent dielectric films such as silicon dioxide, other carbon doped oxides over metal or semiconductor substrates. An index of refraction is measured by an ellipsometer and a wavelength of a laser beam is measured using a laser spectrometer. The angle of refraction is determined by directing a light pulse focused onto a wafer surface, measuring a first set of x1, y1, and z1 coordinates, moving the wafer in the z direction, directing the light pulse onto the wafer surface and measuring a second set of x2, y2 and z2 coordinates, using the coordinates to calculate an angle of incidence, calculating an angle of refraction from the calculated angle of incidence, obtaining a sound velocity v, from the calculated angle of refraction and using the determined sound velocity v, to calculate a bulk modulus.

Abstract: An optical system includes both a microspot broadband spectroscopic ellipsometer and a photoacoustic film thickness measurement system that are supplied laser light by the same laser light source. One of the systems makes a measurement, the result of which is used to adjust a parameter of the other system; e.g. the ellipsometer measures thickness and the photoacoustic system uses the thickness result to measure the speed of sound. In one version, the ellipsometer converts the laser beam to a broad-spectrum beam that provides higher intensity.

Abstract: An optical system includes both a microspot broadband spectroscopic ellipsometer and a photoacoustic film thickness measurement system that are supplied laser light by the same laser light source. One of the systems makes a measurement, the result of which is used to adjust a parameter of the other system; e.g. the ellipsometer measures thickness and the photoacoustic system uses the thickness result to measure the speed of sound. In one version, the ellipsometer converts the laser beam to a broad-spectrum beam that provides higher intensity.

Abstract: An apparatus for improving the signal to noise ratio of measurements of the thickness of layers in a thin film stack uses a photoacoustic measurement system that includes a time differentiation system for inducing a delay in pump beam pulses. The time differentiation system uses, among other things, a birefringent element and other elements to control the polarization of pump beam pulses. Use of the apparatus involves applying a time varying voltage to an electro-optic modulator driver and setting a time differentiation step; or, in another embodiment, applying a time varying voltage to an electro-optic modulator to induce a fixed time delay delta-t between a vertically polarized pulse and a horizontally polarized pulse. The high frequency operation of the system provides for improved determinations of film thickness.

Abstract: Disclosed are methods and apparatus for reducing thermal loading of a film disposed on a surface of a sample, such as a semiconductor wafer, while obtaining a measurement of a thickness of the film in an area about a measurement site. The method includes steps of (a) bringing an optical assembly of the measurement system into focus; (b) aligning a beam spot with the measurement site; (c) turning on one of a dither EOM or a dither AOM or a piezo-electric dither assembly to sweep the beam spot in an area about the measurement site, thereby reducing the thermal loading within the measurement site; (d) making a measurement by obtaining a signal representing an average for the film under the area; (e) recording the measurement data; and (f) analyzing the measurement data to determine an average film thickness in the measurement area.

Abstract: Disclosed are methods and apparatus for reducing thermal loading of a film disposed on a surface of a sample, such as a semiconductor wafer, while obtaining a measurement of a thickness of the film in an area about a measurement site. The method includes steps of (a) bringing an optical assembly of the measurement system into focus; (b) aligning a beam spot with the measurement site; (c) turning on one of a dither EOM or a dither AOM or a piezo-electric dither assembly to sweep the beam spot in an area about the measurement site, thereby reducing the thermal loading within the measurement site; (d) making a measurement by obtaining a signal representing an average for the film under the area; (e) recording the measurement data; and (f) analyzing the measurement data to determine an average film thickness in the measurement area.