A method for performing a lithography process is provided. The method includes forming a photoresist layer over a substrate, providing a plurality of target droplets to a source vessel, and providing a plurality of first laser pulses according to a control signal provided by a controller to irradiate the target droplets in the source vessel to generate plasma as an EUV radiation. The plasma is generated when the control signal indicates a temperature of the source vessel is within a temperature threshold value. The method further includes directing the EUV radiation from the source vessel to the photoresist layer to form a patterned photoresist layer and developing and etching the patterned photoresist layer to form a circuit layout.

An extreme ultraviolet light generation apparatus includes a target supply unit configured to output a droplet target into a chamber device, a prepulse laser light irradiation system configured to irradiate the droplet target with prepulse laser light having linear polarization to generate a diffusion target, and a main pulse laser light irradiation system configured to irradiate the diffusion target with main pulse laser light to generate extreme ultraviolet light. Here, a cross section perpendicular to an optical axis of the main pulse laser light when being radiated to the diffusion target having a shape longer in a polarization direction of the prepulse laser light when being radiated to the droplet target than in directions other than the polarization direction.

A method of determining representative patterns for training a machine learning model to predict optical proximity corrections. The method includes obtaining a design layout including a set of groups of patterns, each group of patterns includes one or more sub-groups; determining a set of representative patterns of the set of groups of patterns, a representative pattern being a sub-group whose instances appear in the set of groups of patterns; obtaining, via simulating an optical proximity correction process using the set of representative patterns, optical proximity correction data associated with the set of representative patterns; and training a machine learning model to predict optical proximity corrections for the design layout based on the set of representative patterns and the set of optical proximity correction data.

A processing apparatus includes a driver configured to drive a controlled object, and a controller configured to control the driver by generating a command value to the driver based on a control error. The controller includes a first compensator configured to generate a first command value based on the control error, a second compensator configured to generate a second command value based on the control error, and an adder configured to obtain the command value by adding the first command value and the second command value. The second compensator includes a neural network for which a parameter value is decided by learning, and input parameters input to the neural network include at least one of a driving condition of the driver and an environment condition in a periphery of the controlled object in addition to the control error.

Provided is a method for forming a photoresist pattern, in which a silicon oxide layer is formed on a substrate. A first photoresist pattern, which contacts the silicon oxide layer, is formed on the silicon oxide layer. Entire-surface exposure is performed on the substrate on which the first photoresist pattern having a defect is formed. The first photoresist pattern is entirely removed by developing the first photoresist pattern, which has been subject to the entire-surface exposure. In addition, a second photoresist pattern is formed on the silicon oxide layer.

An apparatus for reducing hydrogen permeation of a mask is provided when generating extreme ultraviolet (EUV) radiation. The apparatus includes a mask stage configured to hold the mask, a hydrogen dispensing nozzle configured to eject hydrogen below the mask, and a trajectory correcting assembly. The trajectory correcting assembly includes a correcting nozzle and a gas flow detector. The correcting nozzle is configured to dispense at least one flow adjusting gas to adjust a trajectory of the hydrogen away from the mask to reduce hydrogen permeation at an edge of the mask. The gas flow detector is configured to measure a variation of an airflow of the hydrogen adjusted by the at least one flow adjusting gas.

Some implementations herein include a detection circuit and a fast and accurate in-line method for detecting blockage on a droplet generator head of an extreme ultraviolet exposure tool without impacting the flow of droplets of a target material through the droplet generator head. In some implementations described herein, the detection circuit includes a switch circuit that is configured in an open configuration, in which the switch is electrically open between two electrode elements. When an accumulation of the target material occurs across two or more electrode elements on the droplet generator head, the accumulation functions as a switch that closes the detection circuit. A controller may detect closure of the detection circuit.

A system for a semiconductor fabrication facility includes a maintenance tool, a control unit, a first track, a second track, a maintenance crane movably mounted on the first track, a plurality of first sensors disposed on the first track, an OHT vehicle movably mounted on the second track, and a second sensor on the OHT vehicle. The first sensors detect a location of the maintenance crane and generate a first location data to the control unit. The second sensor generates a second location data to the control unit.

A light source for EUV radiation is provided. The light source includes a target droplet generator, a laser generator, and a controller. The target droplet generator is configured to provide target droplets to a source vessel. The laser generator is configured to provide a plurality of first laser pulses according to a control signal to irradiate the target droplets in the source vessel to generate plasma as the EUV radiation. The controller is configured to provide the control signal according to the temperature of the source vessel and droplet positions of the target droplets. When the temperature of the source vessel exceeds a temperature threshold value and a standard deviation of the droplet positions of the target droplets exceeds a first standard deviation threshold value, the controller is configured to provide the control signal to the laser generator, so as to stop providing the first laser pulses.

A method for determining a correction to a patterning process. The method includes obtaining a plurality of qualities of the patterning process (e.g., a plurality of parameter maps, or one or more corrections) derived from metrology data and data of an apparatus used in the patterning process, selecting, by a hardware computer system, a representative quality from the plurality of qualities, and determining, by the hardware computer system, a correction to the patterning process based on the representative quality.