Laser gas replenishment method

A gas discharge laser system, comprising:

• a discharge chamber containing a laser gas mixture including a constituent gas which is subject to depletion;
• a plurality of electrodes connected to a power supply circuit for providing a driving voltage to said electrodes to generate a pulsed discharge to energize said laser gas mixture;
• a resonator surrounding said discharge chamber for generating a pulsed laser beam;
• a gas supply unit connected to said discharge chamber;
• and
• a processor for controlling gaseous flow between said gas supply unit and said discharge chamber,
• wherein said gas supply unit and said processor are configured to permit between 0.0001 mbar and 0.2 mbar of said constituent gas to inject into said discharge chamber at selected intervals, and
• wherein said intervals are varied based on a value of the driving voltage applied to achieve a predetermined output pulse energy.

A method for controlling a composition of a gas mixture within a discharge chamber of a gas discharge laser system, comprising the steps of:

• monitoring an input driving voltage of a pulse power circuit of the laser;
• monitoring a second parameter indicative of the concentration of a constituent gas of the gas mixture;
• determining an amount of constituent gas between 0.0001 mbar and 0.2 mbar to be injected into said discharge chamber based on a value of the driving voltage applied to achieve a predetermined output pulse energy;
• and
• injecting said amount of said constituent gas into said discharge chamber at selected intervals when a predetermined value of said second parameter is reached.

A method for controlling a composition of a gas mixture within a discharge chamber of a gas discharge laser system, comprising the steps of:

• monitoring an input driving voltage of a pulse power circuit of the laser;
• monitoring a second parameter indicative of the concentration of a constituent gas of the gas mixture;
• determining an interval value of said second parameter between which injections into the discharge chamber of said constituent gas between 0.0001 mbar and 0.2 mbar are performed based on a value of the driving voltage applied to achieve a predetermined output pulse energy;
• and
• injecting said constituent gas into said discharge chamber at said interval when a predetermined value of said second parameter based on said predetermined interval is reached.

A gas discharge laser system, comprising:

• a discharge chamber containing a laser gas mixture including a halogen gas which is subject to depletion;
• a plurality of electrodes connected to a power supply circuit for providing a driving voltage to said electrodes as a pulsed discharge to energize said laser gas mixture;
• a resonator surrounding said discharge chamber for generating a pulsed laser beam;
• a gas supply unit connected to said discharge chamber;
• and
• a processor for controlling gaseous flow between said gas supply unit and said discharge chamber,
• wherein said gas supply unit and said processor are configured to permit a quantity less than 5% of said halogen gas in said discharge chamber to inject into said discharge chamber at selected intervals, and
• wherein an amount of halogen gas injected is varied based on a value of the driving voltage applied to achieve a predetermined output pulse energy.

A gas discharge laser system, comprising:

• a discharge chamber containing a laser gas mixture including a halogen gas which is subject to depletion;
• a plurality of electrodes connected to a power supply circuit for providing a driving voltage to said electrodes to generate a pulsed discharge to energize said laser gas mixture;
• a resonator surrounding said discharge chamber for generating a pulsed laser beam;
• a gas supply unit connected to said discharge chamber;
• and
• a processor for controlling gaseous flow between said gas supply unit and said discharge chamber,
• wherein said gas supply unit and said processor are configured to permit a quantity less than 5% of said halogen gas in said discharge chamber to inject into said discharge chamber at selected intervals, and
• wherein said intervals are varied based on a value of the driving voltage applied to achieve a predetermined output pulse energy.

A method for controlling a composition of a gas mixture within a discharge chamber of a gas discharge laser system, comprising the steps of:

• monitoring an input driving voltage of a pulse power circuit of the laser;
• monitoring a second parameter indicative of the concentration of a halogen gas of the gas mixture;
• determining an amount of halogen gas less than 5% of said halogen gas in said discharge chamber to be injected into said discharge chamber based on a value of the driving voltage applied to achieve a predetermined output pulse energy;
• and
• injecting said amount of said halogen gas into said discharge chamber at selected intervals when a predetermined value of said second parameter is reached.

A method for controlling a composition of a gas mixture within a discharge chamber of a gas discharge laser system, comprising the steps of:

• monitoring an input driving voltage of a pulse power circuit of the laser;
• monitoring a second parameter indicative of the concentration of a halogen gas of the gas mixture;
• determining an interval value of said second parameter between which injections into the discharge chamber of said halogen gas in an amount less than 5% of said halogen gas in said discharge chamber are performed based on a value of the driving voltage applied to achieve a predetermined output pulse energy;
• and
• injecting said halogen gas into said discharge chamber at said interval when a predetermined value of said second parameter based on said predetermined interval is reached.