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AssigneeSiemens Aktiengesellschaft
InventorsTheo Troukens, Antoon Mattelin
Estimating the term…
A method and apparatus for adjusting the reference system of a pre-programmable laser device relative to the position of an inscription field of a part to be processed such as a silicon wafer characterized by a laser beam from a laser operating in a continuous wave mode being programmed to travel in various search motions with each motion traversing and passing over an edge of the part. The light which is unblocked by the part is received by a photoelectric element to trigger a position signal for each time the light passes across the edge of the wafer. The precise position of the wafer or part relative to the reference system is calculated from the position signals with the assistance of a computer and subsequently the coordinates of the reference system are corrected to match the precise position of the part.
In a method for adjusting a reference system of a pre-programmable beam deflection system of a processing device having a processing laser operable in a giant pulse mode with respect to a position of the inscription field of a part to be processed, particularly a silicon wafer, said method of adjusting including conducting a plurality of programmed search motions with a laser beam from a laser operating in a continuous wave mode, detecting light signals with photoelectric elements during each search motion, and then calculating precise positions of the part with respect to the reference system from the detected light signals and correcting the coordinates of the reference system in response to the calculated positions, the improvements comprising each of the search motions being directed to travel in a path across an edge of said part, said step of detecting including positioning each of the photoelectric elements beneath the part adjacent the edge in the path of the search motion and detecting the light that is not blocked by the part to trigger a corresponding position signal as the laser beam passes across the edge of the part and said step of calculating includes evaluating the position signals for correcting the coordinate of the reference system.
In a device for adjusting the reference system of a pre-progammable beam deflection system of a laser processing device with respect to the position of an inscription field of a part to be processed, said device for adjusting including means for conducting a plurality of programmed search motions of a laser beam from a laser operating in a continuous wave mode, photoelectric elements positioned to detect light signals during each search motion, means for calculating the precise position of the part with respect to the reference system from the detected light signals and means for correcting the coordinates of the reference system in response to the precise position, the improvements comprising the means for conducting a plurality of program search motions having each search motion traveling in a path that traverses an edge of the part being processed and each of the photoelectric elements being disposed below the part and in a path to receive the scanning light as the scanning motion passes over the edge of the part to trigger a corresponding position signal.
Dependencies are inferred from the claim text.