Abstract: A high repetition rate, compact, modular gas discharge, ultraviolet laser. The laser is useful as a light source for very rapid inspections of wafers in an integrated circuit fabrication process. It is also useful for reticle writing at very rapid rates. A preferred embodiment operates at pulse repetition rates of 1000 to 4000 Hz and is designed for round-the-clock production line operation. This preferred embodiment comprises a pulse control unit which controls the timing of pulses to an accuracy of less than 4 nanoseconds. Preferred embodiments of this gas discharge laser can be configured to operate with a KrF gas mixture, an ArF gas mixture or an F2 gas mixture, each with an approximate buffer gas, producing 248 nm, 197 nm or 157 nm ultraviolet light pulses.

Abstract: In an apparatus and method for generating high power laser radiation, the geometry of the resonant laser cavity defines a fundamental spatial or transverse cavity mode. A gain medium is disposed within the resonant cavity and an energy source energizes the gain medium within a first volume. This causes spontaneous and stimulated energy emission to propagate in the gain medium in a direction transverse to the fundamental cavity mode. The transverse emission in turn optically pumps a second volume of the gain medium about the first volume. When the intensity of the transverse emission is sufficiently high, inversion and gain are produced in the second volume. By optimizing the geometry of the cavity such that the fundamental cavity mode is coupled to both the first and the second volumes encompassing the first pumped volume, the transversely-directed energy of the first volume which would otherwise be wasted is instead captured by the fundamental beam, improving the overall power efficiently of the laser.

Abstract: A laser source (1) includes a pumping system (2) and an active element (3) which comprises a doped elongate rod (4) and at least one optical block (5, 6) for guiding the pump rays (F) of at least one pump beam toward the rod (4). The pumping system (2) generates a number of parallel pump rays (F). The entry face (5A, 6A) of the optical block (5, 6) is inclined to the longitudinal axis (X—X) of the rod (4) and is not orthogonal to the pump rays (F) in order to deflect the pump rays (F) by refraction so as to transmit them toward the rod (4), and the inclination of the entry face (5A, 6A) is such that the pump rays (F) reach the bar (4) so as to be distributed over its entire length.

Abstract: An excimer or molecular fluorine laser system includes a discharge chamber filled with a gas mixture including a halogen-containing molecular species and at least one noble gas including a buffer gas, multiple electrodes within the discharge chamber and connected to a pulsed power supply circuit for energizing the gas mixture, and a resonator for generating an output beam. The resonator includes the discharge chamber and one or more optics for narrowing a bandwidth of the beam and for magnifying the beam in each of orthogonal beam axis directions for suppressing fluctuations in one or more output beam parameters.

Abstract: In a semiconductor laser, non-disordered quantum well active region functions as a lasing region. Surrounding the non-disordered quantum well active region is a disordered quantum well active region which prevents diffusion of injected carriers from the non-disordered quantum well active region or provides a lateral heterobarrier. The disordered quantum well active region is formed by rapid thermal annealing in which defects from one or two InP defect layers diffuse into the parts of the quantum well active region to be disordered.

Abstract: In a mode locking semiconductor laser that generates an ultra short optical pulse train with a frequency corresponding to a reference frequency, an active wave guiding channel to which a modulation signal at the reference frequency is applied, a passive wave guiding channel which is transparent to oscillation light and an ohmic resistance heating film provided over the passive wave guiding channel that generates Joule heat based upon an current injected thereto and changes the refractive index of the passive wave guiding channel to change the optical length are formed to constitute an optical resonator.

Abstract: Power density profile of a laser beam is characterized by scanning a thin thread across the beam and registering the intensity of radiation scattered from the thread. The diameter of the beam along the scan direction is determined by measuring the width of the signal received from the scattered power for the given speed of the thread across the beam.