Abstract:
A lithographic apparatus includes at least one image alignment sensor for receiving radiation projected from an alignment mark on a reticle. Processor processes signals from the sensor(s) to resolve spatial information in the projected alignment mark to establish a reference for measuring positional relationships between a substrate support and the patterning location. Examples of the sensor include line arrays of photodetectors. A single array can resolve spatial information in a plane of the sensor (X, Y direction) and in a perpendicular (Z) direction. At least a final step in establishing the reference position is performed while holding the substrate support stationary. Errors and delays induced by mechanical scanning of prior art sensors are avoided. Alternatively (not illustrated) the sensor is moved for mechanical scanning relative to the substrate support, independently of the main positioning systems.
Abstract:
The present invention relates to a stage system (130), which comprises a pre-exposure element (134), and to a method employing the pre-exposure element for conditioning an optical system (100). The pre-exposure element comprises a radiation receiving area at a surface of the stage system, wherein the radiation receiving area comprises at least one pre-exposure plate configured to receive radiation. The stage system comprises further a controller (140), wherein the controller is capable to control an optical parameter of the pre-exposure element, herewith controlling a portion of received radiation reflected by the pre-exposure element.
Abstract:
A lithographic apparatus and associated method of controlling a lithographic process. The lithographic apparatus has a controller configured to define a control grid associated with positioning of a substrate within the lithographic apparatus. The control grid is based on a device layout, associated with a patterning device, defining a device pattern which is to be, and/or has been, applied to the substrate in a lithographic process.
Abstract:
A method is provided for determining surface parameters of a patterning device, comprising the steps of: positioning the patterning device with respect to a path of an exposure radiation beam using a first measurement system, providing the patterning device at a first focal plane of a chromatic lens arranged in a second measurement system, illuminating a part of a surface of the patterning device with radiation through the chromatic lens, wherein the radiation comprises a plurality of wavelengths, determining a position of the illuminated part of the patterning device in a first and second direction, collecting at least a portion of radiation reflected by the patterning device through the chromatic lens, measuring an intensity of the collected portion of radiation as a function of wavelength, to obtain spectral information of the illuminated area, and determining the surface parameters of the patterning device at the determined position from the spectral information.
Abstract:
A method of predicting deflection of a pellicle which will occur during movement of the pellicle in a lithographic apparatus, the method including receiving parameters regarding properties of the pellicle and receiving parameters regarding the expected movement of the pellicle. The parameters are applied to a model which predicts deflection of the pellicle as a function of those parameters. The model includes a plurality of sub-models which relate to different components of deflection of the pellicle. An output of the model may be used to predict.
Abstract:
A method of reducing effects of heating and/or cooling a reticle in a lithographic process includes conditioning the reticle to adjust an initial temperature of the reticle to a predetermined temperature, reducing stress in the reticle to reduce parasitic thermal effects, calibrating a reticle heating model by exposing the reticle and a non-production substrate to a dose of radiation, and processing a production substrate by exposing the reticle and a production substrate to a dose of radiation based on the reticle heating model. The method can increase calibration accuracy and speed of the reticle heating model, reduce conditioning times of the reticle, reduce stress in the reticle, avoid rework of production substrates, and increase throughput, yield, and accuracy.
Abstract:
A lithographic apparatus and associated method of controlling a lithographic process. The lithographic apparatus has a controller configured to define a control grid associated with positioning of a substrate within the lithographic apparatus. The control grid is based on a device layout, associated with a patterning device, defining a device pattern which is to be, and/or has been, applied to the substrate in a lithographic process.
Abstract:
An apparatus including an illumination system to condition a radiation beam, a support to support a patterning device, the patterning device capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam, a substrate table constructed to hold a substrate, a projection system to project the patterned radiation beam onto a target portion of the substrate, and a control system configured to: receive pattern data characterizing a pattern distribution, receive radiation data characterizing the radiation beam, determine a dissipation distribution of the pattern based on the pattern data and the radiation data, determine deformation of the pattern by applying the dissipation distribution in a thermo-mechanical model of the patterning device, and determine a control signal to control a component of the apparatus based on the deformation of the pattern.
Abstract:
A system and method are provided for determining deformation of a patterning device and/or shift position of the patterning device relative. The system includes a first sensing sub-system that measures respective positions of a plurality of reference marks on the patterning device, and a second sensing sub-system that measures positions of the edge of the patterning device relative to the support. The system further includes a controller to determine an absolute position of the patterned portion and change in the absolute position based on measured respective positions of marks on the patterning device, determine a change in a relative position of the edge of the patterned device based on the measured edge positions, and estimate a change in a position of the patterning device relative to the support and a change in a pattern distortion of the patterned portion of the patterning device over a time period.