Abstract: Metrology tools and methods are provided, which estimate the effect of topographic phases corresponding to different diffraction orders, which result from light scattering on periodic targets, and adjust the measurement conditions to improve measurement accuracy. In imaging, overlay error magnification may be reduced by choosing appropriate measurement conditions based on analysis of contrast function behavior, changing illumination conditions (reducing spectrum width and illumination NA), using polarizing targets and/or optical systems, using multiple defocusing positions etc. On-the-fly calibration of measurement results may be carried out in imaging or scatterometry using additional measurements or additional target cells.

Abstract: Methods and systems for estimating values of process parameters based on measurements of structures fabricated on a product wafer are presented herein. Exemplary process parameters include lithography dosage and exposure and lithography scanner aberrations. A measurement model is employed to estimate process parameter values from measurements of structures fabricated on a wafer by a particular fabrication process. The measurement model includes process parameters and geometric parameters of structures under measurement. In some embodiments, a model based regression of both a process model and a metrology model is employed to arrive at estimates of at least one process parameter value based on measurements of a fabricated structure. In some embodiments, a trained measurement model is employed to directly estimate process parameter values based on measurements of structures.

Abstract: Methods and systems for x-ray based semiconductor metrology utilizing a clean, hard X-ray illumination source are described herein. More specifically, a laser produced plasma light source generates high brightness, hard x-ray illumination having energy in a range of 25,000 to 30,000 electron volts. To achieve high brightness, a highly focused, very short duration laser beam is focused onto a dense Xenon target in a liquid or solid state. The interaction of the focused laser pulse with the high density Xenon target ignites a plasma. Radiation from the plasma is collected by collection optics and is directed to a specimen under measurement. The resulting plasma emission is relatively clean because of the use of a non-metallic target material. The plasma chamber is filled with Xenon gas to further protect optical elements from contamination. In some embodiments, evaporated Xenon from the plasma chamber is recycled back to the Xenon target generator.

Abstract: Methods and systems for focusing and measuring by mean of an interferometer device, having an optical coherence tomography (OCT) focusing system, by separately directing an overlapped measurement and reference wavefront towards a focus sensor and towards an imaging sensor; where a predefined focusing illumination spectrum of the overlapped wavefront is directed towards the focus sensor, and where a predefined measurement illumination spectrum of the overlapped wavefront is directed towards the imaging sensor. Methods and systems for maintaining focus of an interferometer device, having an OCT focusing system, during sample's stage moves.

Abstract: A method for measurement of misregistration in the manufacture of semiconductor device wafers, the method including measuring misregistration between layers of a semiconductor device wafer at a first instance and providing a first misregistration indication, measuring misregistration between layers of a semiconductor device wafer at a second instance and providing a second misregistration indication, providing a misregistration measurement difference output in response to a difference between the first misregistration indication and the second misregistration indication, providing a baseline difference output and ameliorating the difference between the misregistration measurement difference output and the baseline difference output.

Abstract: Electron gun systems with a particular inner width dimension, sweep electrodes, or a combination of a particular inner width dimension and sweep electrodes are disclosed. The inner width dimension may be less than twice a value of a Larmor radius of secondary electrons in a channel downstream of a beam limiting aperture, and a Larmor time for the secondary electrons may be greater than 1 ns. The sweep electrode can generates an electric field in a drift region, which can increase kinetic energy of secondary electrons in the channel.

Abstract: A noise map is used for defect detection. One or more measurements of intensities at one or more pixels are received and an intensity statistic is determined for each measurement. The intensity statistics are grouped into at least one region and stored with at least one alignment target. A wafer can be inspected with a wafer inspection tool using the noise map. The noise map can be used as a segmentation mask to suppress noise.

Abstract: A three-dimensional (3D) microscope includes various insertable components that facilitate multiple imaging and measurement capabilities. These capabilities include Nomarski imaging, polarized light imaging, quantitative differential interference contrast (q-DIC) imaging, motorized polarized light imaging, phase-shifting interferometry (PSI), and vertical-scanning interferometry (VSI).

Abstract: For three-dimensional topography measurement of a surface of an object patterned illumination is projected on the surface through an objective. A relative movement between the object and the objective is carried out, and plural images of the surface are recorded through the objective by a detector. The direction of the relative movement includes an oblique angle with an optical axis of the objective. Height information for a given position on the surface is derived from a variation of the intensity recorded from the respective position. Also, patterned illumination and uniform illumination may be projected alternatingly on the surface, while images of the surface are recorded during a relative movement of the object and the objective along an optical axis of the objective. Uniform illumination is used for obtaining height information for specular structures on the surface, patterned illumination is used for obtaining height information on other parts of the surface.

Abstract: Metrology methods and tools are provided, which enhance the accuracy of the measurements and enable simplification of the measurement process as well as improving the correspondence between the metrology targets and the semiconductor devices. Methods comprise illuminating the target in a Littrow configuration to yield a first measurement signal comprising a ?1st diffraction order and a 0th diffraction order and a second measurement signal comprising a +1st distraction order and a 0th diffraction order, wherein the ?1st diffraction order of the first measurement signal and the +1st diffraction order of the second measurement signal are diffracted at 180° to a direction of the illumination, performing a first measurement of the first measurement signal and a second measurement of the second measurement signal, and deriving metrology metric(s) therefrom. Optionally, a reflected 0th diffraction order may be split to yield components which interact with the ?1st and +1st diffraction orders.

Abstract: Disclosed are methods and apparatus for inspecting a photolithographic reticle. A plurality of reference far field images are simulated by inputting a plurality of reference near field images into a physics-based model, and the plurality of reference near field images are generated by a trained deep learning model from a test portion of the design database that was used to fabricate a test area of a test reticle. The test area of a test reticle, which was fabricated from the design database, is inspected for defects via a die-to-database process that includes comparing the plurality of reference far field reticle images simulated by the physic-based model to a plurality of test images acquired by the inspection system from the test area of the test reticle.

Abstract: An initial inspection or critical dimension measurement can be made at various sites on a wafer. The location, design clips, process tool parameters, or other parameters can be used to train a deep learning model. The deep learning model can be validated and these results can be used to retrain the deep learning model. This process can be repeated until the predictions meet a detection accuracy threshold. The deep learning model can be used to predict new probable defect location or critical dimension failure sites.

Abstract: Systems and methods increase the signal to noise ratio of optical inspection of wafers to obtain higher inspection sensitivity. The computed reference image can minimize a norm of the difference of the test image and the computed reference image. A difference image between the test image and a computed reference image is determined. The computed reference image includes a linear combination of a second set of images.

Abstract: Disclosed herein are optical elements and methods for making the same. Such optical elements may comprise a first layer disposed on a substrate, a second layer disposed on the first layer, a terminal layer disposed on the second layer, and a cap layer disposed on the terminal layer. The cap layer may comprise boron, boron nitride, or boron carbide. Such optical elements may be made using a method comprising depositing a first layer using vapor deposition such that the first layer is disposed on a substrate, depositing a second layer using vapor deposition such that the second layer is disposed on the first layer, depositing a terminal layer using vapor deposition such that the terminal layer is disposed on the second layer, and depositing a cap layer comprising boron, boron nitride, or boron carbide using vapor deposition such that the cap layer is disposed on the terminal layer.

Abstract: Disclosed are methods and apparatus for inspecting a photolithographic reticle. A near field reticle image is generated via a deep learning process based on a reticle database image produced from a design database, and a far field reticle image is simulated at an image plane of an inspection system via a physics-based process based on the near field reticle image. The deep learning process includes training a deep learning model based on minimizing differences between the far field reticle images and a plurality of corresponding training reticle images acquired by imaging a training reticle fabricated from the design database, and such training reticle images are selected for pattern variety and are defect-free.

Abstract: Resistivity probes can be used to test integrated circuits. In one example, a resistivity probe has a substrate with multiple vias and multiple metal pins. Each of the metal pins is disposed in one of the vias. The metal pins extend out of the substrate. Interconnects provide an electrical connection to the metal pins. In another example, a resistivity probe has a substrate with a top surface and multiple elements extending from the substrate. Each of the elements curves from the substrate to a tip of the element such that each of the elements is non-parallel to the top surface of the substrate.

Abstract: Metrology methods and targets are provided, that expand metrological procedures beyond current technologies into multi-layered targets, quasi-periodic targets and device-like targets, without having to introduce offsets along the critical direction of the device design. Machine learning algorithm application to measurements and/or simulations of metrology measurements of metrology targets are disclosed for deriving metrology data such as overlays from multi-layered target and corresponding configurations of targets are provided to enable such measurements. Quasi-periodic targets which are based on device patterns are shown to improve the similarity between target and device designs. Offsets are introduced only in non-critical direction and/or sensitivity is calibrated to enable, together with the solutions for multi-layer measurements and quasi-periodic target measurements, direct device optical metrology measurements.

Abstract: Wafer inspection with stable nuisance rates and defect of interest capture rates are disclosed. This technique can be used for discovery of newly appearing defects that occur during the manufacturing process. Based on a first wafer, defects of interest are identified based on the classified filtered inspection results. For each remaining wafer, the defect classifier is updated and defects of interest in the next wafer are identified based on the classified filtered inspection results.

Abstract: A device and method for expediting spectral measurement in metrological activities during semiconductor device fabrication through interferometric spectroscopy of white light illumination during calibration, overlay, and recipe creation.

Abstract: Real-time job distribution software architectures for high bandwidth, hybrid processor computation systems for semiconductor inspection and metrology are disclosed. The imaging processing computer architecture can be scalable by changing the number of CPUs and GPUs to meet computing needs. The architecture is defined using a master node and one or more worker nodes to run image processing jobs in parallel for maximum throughput. The master node can receive input image data from a semiconductor wafer or reticle. Jobs based on the input image data are distributed to one of the worker nodes. Each worker node can include at least one CPU and at least one GPU. The image processing job can contain multiple tasks, and each of the tasks can be assigned to one of the CPU or GPU in the worker node using a worker job manager to process the image.