Beam position control for an extreme ultraviolet light source

An extreme ultraviolet light system comprising:

• a source that produces an irradiating amplified light beam;
• a steering system that steers and focuses the irradiating amplified light beam toward a target material in a vacuum chamber;
• a beam positioning system comprising:
• one or more optical elements positioned to receive a reflected amplified light beam that is reflected from the target material and to direct the reflected amplified light beam into first, second, and third channels, the first, second, and third channels being three separate paths along which light propagates;
• a first sensor that senses light from the first channel;
• a second sensor, comprising a two-dimensional imaging sensor, that senses light from the second channel and the third channel, the second sensor having a lower acquisition rate than the first sensor;
• and
• an electronic processor coupled to a computer-readable storage medium, the medium storing instructions that, when executed, cause the processor to:
• receive data from the first sensor and the second sensor, and
• determine, based on the received data, a location of the irradiating amplified light beam relative to the target material in more than one dimension.