Laser system for processing a memory link with a set of at least two laser pulses
AssigneeElectro Scientific Industries, Inc.
InventorsYunlong Sun, Edward J. Swenson, Richard S. Harris
Life of this patent
Estimating the term…
Abstract
A set (50) of laser pulses (52) is employed to sever a conductive link (22) in a memory or other IC chip. The duration of the set (50) is preferably shorter than 1,000 ns; and the pulse width of each laser pulse (52) within the set (50) is preferably within a range of about 0.1 ps to 30 ns. The set (50) can be treated as a single “pulse” by conventional laser positioning systems (62) to perform on-the-fly link removal without stopping whenever the laser system (60) fires a set (50) of laser pulses (52) at each link (22). Conventional IR wavelengths or their harmonics can be employed.
Claims30
A laser system for severing, at high throughput rates, multiple selected target links in associated ones of multiple electrically conductive link structures fabricated in an integrated circuit, the target links formed with passivation layer material overlying electrically conductive link material, comprising:
- a laser source operable to generate multiple laser pulses for propagation along a beam axis;
- and
- a beam positioning system operable to impart rapid relative motion of the integrated circuit and the beam axis along which the multiple laser pulses propagate, the beam positioning system, in response to position data representative of locations of the multiple electrically conductive link structures, operable to move the beam axis between successive ones of the multiple selected target links and to direct the beam axis to the multiple selected target links so that multiple ones of the laser pulses within a specified duration impinge on the link material of each of the multiple selected target links;
- and
- a controller operable to coordinate control of the rapid relative motion of the integrated circuit and the beam axis and operable to coordinate control of the impingement on the link material of the multiple ones of the laser pulses within the specified duration to successively remove, by interaction of the multiple ones of the laser pulses with the link material and without stopping the beam axis over any one of the multiple selected target links, portions of the overlying passivation layer material and link material to sever the multiple selected target links at a high throughput rate.
Dependencies are inferred from the claim text.