PULSED LASER MICRO-DEPOSITION PATTERN FORMATION

摘要

A method of forming patterns on transparent substrates using a pulsed laser is disclosed. Various embodiments include an ultrashort pulsed laser, a substrate that is transparent to the laser wavelength, and a target plate. The laser beam is guided through the transparent substrate and focused on the target surface. The target material is ablated by the laser and is deposited on the opposite substrate surface. A pattern, for example a gray scale image, is formed by scanning the laser beam relative to the target. Variations of the laser beam scan speed and scan line density control the material deposition and change the optical properties of the deposited patterns, creating a visual effect of gray scale. In some embodiments patterns may be formed on a portion of a microelectronic device during a fabrication process. In some embodiments high repetition rate picoseconds and nanosecond sources are configured to produce the patterns.

主权项

1. A method of pulsed laser deposition to produce a pattern on a medium, said medium being substantially transparent at a wavelength of said pulsed laser, said method comprising:
generating pulsed laser beams from a pulsed laser source; transmitting said pulsed laser beams through said medium; focusing said pulsed laser beams onto a target, said target producing ejecta in response to an interaction of said pulsed beams and said target; scanning said laser beams relative to said medium and target; accumulating at least a portion of said ejecta on said medium to form material deposits on said medium; and varying at least one of a laser beam scan speed and scan line density for controlling thickness of said material deposits to vary an optical density of a region of said medium, and to form a spatial pattern having varying optical density, wherein said laser beam scan speed or said scan line density is varied according the gray scale of the pattern to be printed, the gray scale including at least three gray levels in a digitized image of said pattern.