Abstract: A pulsed laser comprises an oscillator and amplifier. An attenuator and/or pre-compressor may be disposed between the oscillator and amplifier to improve performance and possibly the quality of pulses output from the laser. Such pre-compression may be implemented with spectral filters and/or dispersive elements between the oscillator and amplifier. The pulsed laser may have a modular design comprising modular devices that may have Telcordia-graded quality and reliability. Fiber pigtails extending from the device modules can be spliced together to form laser system. In one embodiment, a laser system operating at approximately 1050 nm comprises an oscillator having a spectral bandwidth of approximately 19 nm. This oscillator signal can be manipulated to generate a pulse having a width below approximately 90 fs.

Abstract: Various embodiments may be used for laser-based modification of target material of a workpiece while advantageously achieving improvements in processing throughput and/or quality. Embodiments of a method of processing may include focusing and directing laser pulses to a region of the workpiece at a pulse width sufficiently short so that material is efficiently removed by nonlinear optical absorption from the region and a quantity of heat affected zone and thermal stress on the material within the region, proximate to the region, or both is reduced relative to a quantity obtainable using a laser with longer pulses. In at least one embodiment, an ultrashort pulse laser system may include at least one of a fiber amplifier or fiber laser. Various embodiments are suitable for at least one of dicing, cutting, scribing, and forming features on or within a composite material.

Abstract: An imaging apparatus uses focusing and collecting optics in combination with steering optics for efficient imaging of a target using an extended terahertz electro-magnetic range challenged by weak sources and low sensitivity of detection. By proper location of optics to utilize angular conversion of the beam to a lateral scan, a rastering imaging apparatus is demonstrated without moving target or entire imaging system. In at least one embodiment a mirror-lens set is used to steer the terahertz (THz) beam along and (or) to collect the THz beam from each point of the target. The target is imaged with a much higher speed than when moving the target or the entire imaging system. A THz wave image can be taken at video frequency for practical usage of the apparatus in diverse application areas, where it has not been considered to be feasible.

Abstract: Various embodiments may be used for laser-based modification of target material of a workpiece while advantageously achieving improvements in processing throughput and/or quality. Embodiments of a method of processing may include focusing and directing laser pulses to a region of the workpiece at a pulse repetition rate sufficiently high so that material is efficiently removed from the region and a quantity of unwanted material within the region, proximate to the region, or both is reduced relative to a quantity obtainable at a lower repetition rate. In at least one embodiment, an ultrashort pulse laser system may include at least one of a fiber amplifier or fiber laser. Various embodiments are suitable for at least one of dicing, cutting, scribing, and forming features on or within a semiconductor substrate.

Abstract: An imaging apparatus uses focusing and collecting optics in combination with steering optics for efficient and speedy imaging of a target using an extended terahertz electro-magnetic range challenged by weak sources and low sensitivity of detection. This invention addresses efficient detection of this wave in combination with a speedy imaging speed. By proper location of optics to utilize angular conversion of the beam to a lateral scan, a rastering imaging apparatus is demonstrated without moving target or entire imaging system. A mirror-lens set is used to steer the terahertz (THz) beam along and (or) to collect the THz beam from each point of the target. The target is imaged with a much higher speed than when moving the target or the entire imaging system. A THz wave image can be taken at video frequency for practical usage of the apparatus in diverse application areas, where it has not been considered to be feasible.

Abstract: A non-contact method for determining the index of refraction or dielectric constant of a thin film on a substrate at a desired frequency in the GHz to THz range having a corresponding wavelength larger than the thickness of the thin film (which may be only a few microns). The method comprises impinging the desired-frequency beam in free space upon the thin film on the substrate and measuring the measured phase change and the measured field reflectance from the reflected beam for a plurality of incident angles over a range of angles that includes the Brewster's angle for the thin film. The index of refraction for the thin film is determined by applying Fresnel equations to iteratively calculate a calculated phase change and a calculated field reflectance at each of the plurality of incident angles, and selecting the index of refraction that provides the best mathematical curve fit with both the dataset of measured phase changes and the dataset of measured field reflectances for each incident angle.