An optical system for producing lithographic structures is disclosed. Also disclosed is a method for determining relative coordinates of a position of a writing field relative to a position of a preview field in such an optical system, and a method for producing lithographic structures using such an optical system.

An alignment system, a dual-wafer-stage system and a measurement system are disclosed, the alignment system including a main frame (201, 301), a first wafer stage (205, 305), an alignment sensor (202, 302), a position acquisition module (208, 308) and a signal processing device (203, 303). The position acquisition module (208, 308) collects positional data from the first wafer stage (205, 305) and the reflector (204, 304) simultaneously. The reflector (204, 304) is arranged on the alignment sensor (202, 302). In other words, positional data of the alignment sensor (202, 302) and positional data of the first wafer stage (205, 305) are collected simultaneously. In addition, the data can be processed to indicate the relative position of the first wafer stage (205, 305) relative to the alignment sensor (202, 302) whose vibration has been zeroed. That is, a position where an alignment mark is aligned can be obtained with the relative vibration amplitude of the alignment sensor (202, 302) being zeroed. This can circumvent the impact of vibration of the alignment sensor (202, 302) and allow increased repeatability accuracy of alignment.

Inspection of microelectronic devices is described using near infrared light. In one example, a dielectric material layer on a substrate is illuminated with a near infrared light beam. The substrate has at least one contact land, the dielectric material layer overlies at least a portion of the contact land, and the substrate has at least one via defined in the dielectric material layer, the via exposing at least a portion of the contact land. Reflected near infrared light is reflected from the substrate at a camera. The position of the via is determined relative to the contact land from the reflected light beam using an image processing device.

Various embodiments of aligning wafers are described herein. In one embodiment, a photolithography system aligns a wafer by averaging individual via locations. In particular, some embodiments of the present technology determine the center locations of individual vias on a wafer and average them together to obtain an average center location of the set of vias. Based on a comparison of the average center location to a desired center location, the present technology adjusts the wafer position. Additionally, in some embodiments, the present technology compares wafer via patterns to a template and adjusts the position of the wafer based on the comparison.

An optical system for producing lithographic structures is disclosed. Also disclosed is a method for determining relative coordinates of a position of a writing field relative to a position of a preview field in such an optical system, and a method for producing lithographic structures using such an optical system.

A broadband spectroscopic analysis is used for controlling a distance (d) between a miniature solid immersion lens (SIL, 60) and a metrology target (30). An objective lens arrangement (15, 60) including the SIL illuminates the metrology target with a beam of radiation with different wavelengths and collects a radiation (709) reflected or diffracted by the metrology target. A mounting (64) holds the SIL within a distance from the metrology target that is less than the coherence length of the illuminating radiation (703). A detection arrangement (812, 818) produces a spectrum of the radiation reflected or diffracted by the metrology target. The distance between the SIL and the metrology target or other target surface can be inferred from spectral shifts observed in the detected spectrum. Servo control of the distance is implemented based on these shifts, using an actuator (66).

A method of forming a pattern includes: preparing a target substrate including a photoresist layer on a base substrate; aligning a phase shift mask to the target substrate, the phase shift mask including a mask substrate comparted into a first region including a first sub region and second sub regions at sides of the first sub region, and second regions at sides of the first region, the phase shift mask including a phase shift layer on the mask substrate corresponding to the first region; fully exposing the photoresist layer at the first sub region and the second regions by utilizing the phase shift mask; and removing the photoresist layer at the first sub region and the second regions to form first and second photoresist patterns corresponding to the second sub regions. Transmittance of the phase shift layer is selected to fully expose the photoresist layer in the first sub region.

Disclosed is a method of measuring a parameter of a lithographic process, and associated computer program and apparatuses. The method comprises providing a plurality of target structures on a substrate, each target structure comprising a first structure and a second structure on different layers of the substrate. Each target structure is measured with measurement radiation to obtain a measurement of target asymmetry in the target structure, the target asymmetry comprising an overlay contribution due to misalignment of the first and second structures, and a structural contribution due to structural asymmetry in at least the first structure. A structural asymmetry characteristic relating to the structural asymmetry in at least the first structure of each target structure is obtained, the structural asymmetry characteristic being independent of at least one selected characteristic of the measurement radiation. The measurement of target asymmetry and the structural asymmetry characteristic is then used to determine the overlay contribution of the target asymmetry of each target structure.

The invention relates to a method for automated determination of a reference point of an alignment mark on a substrate of a photolithographic mask, which method comprises the following steps: (a) performing a first line scan within a start region of the substrate in a first direction on a surface of the substrate, the alignment mark being arranged within the start region, for locating a first element of the alignment mark; (b) performing a second line scan within the start region in at least a second direction, which intersects the first direction, on the surface of the substrate for locating a second element of the alignment mark; (c) estimating the reference point of the alignment mark from the located first element and the located second element of the alignment mark; and (d) imaging a target region around the estimated reference point of the alignment mark in order to determine the reference point of the alignment mark, with the imaging being carried out at a higher resolution than the performance of the line scans in steps (a) and (b).

A lithography method of forming, on a substrate, a plurality of layers including a first layer including a first pattern, a second layer including a second pattern, and a third layer, is provided. The method includes detecting relative position information indicating relative position between the first pattern and the second pattern in aligning the substrate and an original for patterning of the third layer. The method also includes collecting the relative position information obtained in the detecting.