Kla Corporation

Asaf Granot

Amnon Manassen

Andrei V Shchegrov

Andrew V Hill

Avi Abramov

An optical inspection apparatus includes an illumination assembly, configured to direct optical radiation to illuminate a semiconductor wafer on which first and second patterned layers have been deposited in succession, including a first target feature in the first patterned layer and a second target feature in the second patterned layer, such that at least one of the first and second target features has at least one dimension in the plane of the wafer that is less than an optical diffraction limit of the apparatus. An imaging assembly is configured to capture at least one image of the wafer, and a controller is configured to process the at least one image in order to identify respective locations of the first and second target features in the at least one image and to measure an overlay error between the first and second patterned layers responsively to a displacement between the respective locations.

Sub-resolution imaging target

A system and method for generating a quality metric relating to a fully or partially fabricated semiconductor device wafer (FPFSDW), the method including providing a spot map correlating a plurality of reference field images (RFIs) to a corresponding plurality of reference spot locations (RSLs) on at least one reference structure formed on a reference semiconductor device wafer, taking a measurement of at least a portion of at least one FPFSDW structure formed on the FPFSDW, thereby generating a measurement field image (MFI) of at least a portion of the at least one FPFSDW structure and a pupil image of the at least a portion of the at least one FPFSDW structure, identifying, for the measurement, a measurement spot location (MSL) on the at least one FPFSDW structure, using the MFI and the spot map, and generating a quality metric of the FPFSDW, using the pupil image and the MSL.

Systems and methods for determining measurement location in semiconductor wafer metrology

A metrology measurement apparatus may include one or more illumination sources, a beamsplitter configured to receive illumination from the one or more illumination sources from an illumination pathway and direct the illumination along a measurement pathway, and an objective lens. The objective lens may direct the illumination from the measurement pathway to a sample, collect light from the sample, and direct the collected light along the measurement pathway to the beamsplitter such that the beamsplitter may direct the collected light along a collection pathway to a detector. The apparatus may further include a pupil-plane scanner along the measurement pathway with a pupil relay and a deflector in a relayed pupil plane such that adjusting the deflector adjusts a position of the illumination spot on the sample without modifying a position of the illumination pupil distribution or a position of a distribution of the collected light along the collection pathway.

Pupil-plane beam scanning for metrology

A sample positioning system is disclosed. The system may include an imaging detector. The system may further include a controller communicatively coupled to the imaging detector and a sample stage, the controller including one or more processors configured to execute program instructions causing the one or more processors to: receive a current position of a field of view of the imaging detector; receive a target position of the sample; receive locations of reference features along a path; direct the sample stage to translate the sample along the path; direct the imaging detector to capture images of the reference features along the path; determine positioning errors of the sample stage along the path based on the images of the reference features; and adjust at least one of a velocity of the sample stage or the path to the target location based on the positioning errors during translation.

Growing community of inventors

Lotem, Israel

Asaf Granot