A polarisation and mode selection technique for a gas waveguide laser is described in which a surface of the waveguide is formed to be substantially dielectric with a localised metallic region therein. The metallic region provides linear polarisation while the dielectric surface provides for low order mode selection. Embodiments are described to channel and planar waveguides with various resonator configurations. Ranges are provided for the size and location of the metallic region on the waveguide surface.

Disclosed is a low pressure wire ion plasma discharge source including an elongated ionization chamber housing at least two parallel anode wires extending longitudinally within the ionization chamber. A first of the at least two anode wires is connected to a DC voltage supply and a second of the at least two anode wires is connected to a pulsed voltage supply.

A radio-frequency, RF, slab laser 10 with a Z-fold resonator cavity defined by an output mirror 32, a first fold mirror 34, a second fold mirror 36 and a rear mirror 30. The second fold mirror 36 is rotated by an adjustment angle away from the angle it would have if the mirrors were all plane mirrors and directed the round trip beam path by direct reflection. Moreover, the rear mirror 30 is rotated by an adjustment angle that is approximately twice the adjustment angle of the second fold mirror 36. These rotations of the rear mirror 30 and second fold mirror 36 suppresses parasitic mode paths that would otherwise exist.

A laser irradiation method of irradiating, with a pulse laser beam, an irradiation object in which an impurity source film is formed on a semiconductor substrate includes: reading fluence per pulse of the pulse laser beam with which a rectangular irradiation region set on the irradiation object is irradiated and the number of irradiation pulses the irradiation region is irradiated, the fluence being equal to or larger than a threshold at or beyond which ablation potentially occurs to the impurity source film when the irradiation object is irradiated with pulses of the pulse laser beam in the irradiation pulse number and smaller than a threshold at or beyond which damage potentially occurs to the surface of the semiconductor substrate; calculating a scanning speed Vdx; and moving the irradiation object at the scanning speed Vdx relative to the irradiation region while irradiating the irradiation region with the pulse laser beam at the repetition frequency f.

A laser radiation optical system for laser doping and post-annealing, the laser radiation system including A. a laser apparatus configured to generate pulsed laser light that belongs to an ultraviolet region, B. a stage configured to move a radiation receiving object in an at least one scan direction, the radiation receiving object being an impurity source film containing at least an impurity element as a dopant and formed on a semiconductor substrate, and C. an optical system including a beam homogenizer configured to shape the beam shape of the pulsed laser light into a rectangular shape and generate a beam for laser doping and a beam for post-annealing that differ from each other in terms of a first beam width in the scan direction but have the same second beam width perpendicular to the scan direction.

An excimer laser apparatus according to the present disclosure includes a chamber configured to accommodate a laser gas and a pair of electrodes and generate pulse-oscillating laser light when the gas pressure of the laser gas is controlled in accordance with voltage applied between the pair of electrodes, a power supply configured to apply the voltage between the pair of electrodes, and a controller to which a target value of the spectral linewidth of the laser light is inputted, the controller configured to correct the voltage used to control the gas pressure, when the target value changes from a first target value to a second target value, based on a first function having the second target value as a parameter and control the gas pressure in accordance with the corrected voltage.

A device includes a laser source, an amplifier, an optical sensor and a spectrometer. The laser source is configured to produce a seed laser beam. The amplifier includes gain medium and a discharging unit. The discharging unit is configured to pump the gain medium for amplifying power of the seed laser beam. The optical sensor is coupled to the amplifier and configured for sensing an optical emission generated in the amplifier while the gain medium is discharging. The spectrometer is coupled with the optical sensor and configured to measure a spectrum of the optical emission.

A laser processing method of performing laser processing on a transparent material that is transparent to ultraviolet light by using a laser processing system includes: performing relative positioning of a transfer position of a transfer image and the transparent material in an optical axis direction of a pulse laser beam so that the transfer position is set at a position inside the transparent material at a predetermined depth Zsf from a surface of the transparent material in the optical axis direction; and irradiating the transparent material with the pulse laser beam having a pulse width of 1 ns to 100 ns inclusive and a beam diameter of 10 m to 150 m inclusive at the transfer position.

To cool a capacitor including a first electrode and a second electrode, a capacitor cooling structure includes: a conducting part electrically connected with the first electrode; an insulating part that has a first surface including a first position and a second surface including a second position, and is connected with the conducting part at the first position; a first fastening part configured to fasten the conducting part and the insulating part to each other; and a cooling part connected with the second position facing the first position, the conducting part and the cooling part being electrically insulated from each other by the insulating part.

A device includes a laser source, an amplifier, an optical sensor and a spectrometer. The laser source is configured to produce a seed laser beam. The amplifier includes gain medium and a discharging unit. The discharging unit is configured to pump the gain medium for amplifying power of the seed laser beam. The optical sensor is coupled to the amplifier and configured for sensing an optical emission generated in the amplifier while the gain medium is discharging. The spectrometer is coupled with the optical sensor and configured to measure a spectrum of the optical emission.