摘要:
Focal plane errors across the field of an array of focusing elements are reduced by using a non-planar correction surface, shaped such that focal points of the focusing elements lie closer to a single plane than they would if the correction surface were planar. For example, this can be used when an array of focusing elements is used in a projection system of a lithography system.
摘要:
A lithography apparatus including a projection system configured to project a beam of radiation onto a substrate as an array of sub-beams of radiation and an array of individually controllable elements configured to modulate the sub-beams of radiation. The apparatus also includes a data-path including at least one data manipulation device arranged to at least partly convert data defining a requested pattern to a control signal suitable for controlling the array of individually controllable elements to form substantially the requested pattern on the substrate. The data manipulation device is arranged to carry out the conversion by applying a pseudo-inverted form of a point-spread function matrix to a column vector representing the requested pattern. The point-spread function matrix includes information about the shape and relative position of the point-spread function of each spot to be exposed on the substrate by one of the sub-beams of radiation at a given time.
摘要:
An immersion lithographic apparatus is disclosed which includes a liquid supply system having an inlet configured to supply a liquid to a space between a projection system of the lithographic apparatus and a substrate and an outlet configured to remove at least part of the liquid, the liquid supply system configured to rotate the inlet, the outlet, or both, about an axis substantially perpendicular. to an exposure plane of the substrate.
摘要:
A method and system for determining specific pixel modulation states of a spatial light modulator (SLM) to print a desired pattern on a substrate are disclosed. The method includes selecting at least one super-pixel in an object plane of the desired pattern, the super-pixel being formed of at least two pixels. At least one edge of the desired pattern crosses a boundary within the super-pixel, the at least one edge being defined by specific slope and position parameters relative to the super-pixel. The method also includes (i) forming an interpolation table to tabulate pre-calculated pixel modulation states and (ii) determining the specific pixel modulation states for each of the pixels in accordance with the interpolation table. Disclosed also are a method and system for providing a spatial light modulator (SLM). The SLM includes a plurality of mirrors structured to form groups of super-pixels. Each super-pixel (i) includes two or more mirrors from the plurality of mirrors and (ii) is configured to switch only one pixel of light. Each of the two or more mirrors can be separately actuated.
摘要:
A lithographic apparatus and method in which a relatively high resolution exposure, for example of a repeating pattern, is trimmed using a relatively low resolution exposure. According, a compromise between provision of a high resolution pattern and flexibility in the pattern to be formed is provided.
摘要:
To calibrate a lithographic apparatus having a programmable patterning means, a sensor, such as a CCD, CMOS sensor or photo-diode array, having detector elements larger than the size of a spot corresponding to a single pixel of the programmable patterning means is used. Pixels are selectively activated singly or in groups.
摘要:
To prevent a substrate from expanding significantly to generate overlay errors an exposure operation takes place in two parts. A first part exposes boundary areas and a second part exposes the larger, bulk areas. In one example, a portion of the substrate is fixed and the substrate is exposed progressively from parts furthest from the fixed portions towards the fixed portion. In another example, a plurality of high velocity scans take place instead of a single slow scan, and the substrate is allowed to cool between the high velocity scans. In another example, a lithographic apparatus is heated in order to maintain a temperature differential between the apparatus and the surrounding environment, and to minimize any fluctuation due to the exposing radiation.
摘要:
An apparatus and method are used to form patterns on a substrate. The comprise a projection system, a patterning device, a low-pass filter, and a data manipulation device. The projection system projects a beam of radiation onto the substrate as an array of sub-beams of radiation. The patterning device modulates the sub-beams of radiation to substantially produce a requested dose pattern on the substrate. The low-pass filter operates on pattern data derived from the requested dose pattern in order to form a frequency-clipped target dose pattern that comprises only spatial frequency components below a selected threshold frequency. The data manipulation device produces a control signal comprising spot exposure intensities to be produced by the patterning device, based on a direct algebraic least-squares fit of the spot exposure intensities to the frequency-clipped target dose pattern. In various examples, filters for pattern sharpening, image log slope control, and/or CD biasing can also be used.
摘要:
A method for correcting an exposure parameter of an immersion lithographic apparatus is provided. In the method, an exposure parameter is measured using a measuring beam projected through a liquid between the projection system and a substrate table of the immersion lithographic apparatus and offset is determined based on a change of a physical property impacting a measurement made using the measuring beam to at least partly correct the measured exposure parameter. Also, there is provided an apparatus and method to measure a height of an optical element connected to liquid between the projection system and the substrate table in the immersion lithographic apparatus.
摘要:
Use of a refraction grating to divide a beam of radiation into a plurality of sub-beams that are each directed onto an array of individually controllable elements, modulated thereby and projected onto a substrate as an array of spots.