Abstract: Methods and system for signal sampling using spatial dispersion are disclosed. In an example, a system includes a time-to-wavelength dispersion system configured to generate a wavelength dispersed optical pulse that is modulated according to an input signal, a wavelength-to-space dispersion system configured to spatially disperse the wavelength dispersed optical pulse by wavelength to produce a spatially dispersed optical pulse, a sensor system configured to convert the spatially dispersed optical pulse to electrical signals, the sensor system including a two-dimensional (2D) array of photodetectors, and a processor configured to decode the electrical signals to generate information about the input signal.

Abstract: Methods and system for signal sampling using spatial dispersion are disclosed. In an example, a system includes a time-to-wavelength dispersion system configured to generate a wavelength dispersed optical pulse that is modulated according to an input signal, a wavelength-to-space dispersion system configured to spatially disperse the wavelength dispersed optical pulse by wavelength to produce a spatially dispersed optical pulse, a Fast Fourier Transform (FFT) optical system configured to transform the spatially dispersed optical pulse into a frequency domain transformed optical pulse, a sensor system configured to convert the frequency domain transformed optical pulse to electrical signals, the sensor system including a two-dimensional (2D) array of photodetectors, and a processor configured to determine frequency information about the input signal from the electrical signals.

Abstract: Methods and systems for performing co-located measurements of semiconductor structures with two or more measurement subsystems are presented herein. To achieve a sufficiently small measurement box size, the metrology system monitors and corrects the alignment of the measurement spot of each metrology subsystem with a metrology target to achieve maximum co-location of the measurement spots of each metrology subsystem with the metrology target. In another aspect, measurements are performed simultaneously by two or more metrology subsystems at high throughput at the same wafer location. Furthermore, the metrology system effectively decouples simultaneously acquired measurement signals associated with each measurement subsystem. This maximizes signal information associated with simultaneous measurements of the same metrology by two or more metrology subsystems.

Abstract: Methods and systems for performing co-located measurements of semiconductor structures with two or more measurement subsystems are presented herein. To achieve a sufficiently small measurement box size, the metrology system monitors and corrects the alignment of the measurement spot of each metrology subsystem with a metrology target to achieve maximum co-location of the measurement spots of each metrology subsystem with the metrology target. In another aspect, measurements are performed simultaneously by two or more metrology subsystems at high throughput at the same wafer location. Furthermore, the metrology system effectively decouples simultaneously acquired measurement signals associated with each measurement subsystem. This maximizes signal information associated with simultaneous measurements of the same metrology by two or more metrology subsystems.

Abstract: Methods and systems for performing single wavelength ellipsometry (SWE) measurements with reduced measurement spot size are presented herein. In one aspect, a pupil stop is located at or near a pupil plane in the collection optical path to reduce sensitivity to target edge diffraction effects. In another aspect, a field stop is located at or near an image plane conjugate to the wafer plane in the collection optical path to reduce sensitivity to undesired optical-structural interactions. In another aspect, a linear polarizer acting on the input beam of the SWE system includes a thin, nanoparticle based polarizer element. The nanoparticle based polarizer element improves illumination beam quality and reduces astigmatism on the wafer plane. The pupil and field stops filter out unwanted light rays before reaching the detector. As a result, measurement spot size is reduced and tool-to-tool matching performance for small measurement targets is greatly enhanced.