Electro Scientific Industries, Inc.

Other

Hitachi Global Storage Technologies Netherlands B.v.

Yunlong Sun

Richard S Harris

Edward J Swenson

Brian W Baird

Lei Sun

James N O'Brien

Robert Hainsey

Lian-Cheng Zou

Hisashi Matsumoto

Jay Johnson

Weisheng Lei

Manoj Kumar Sammi

Michael J Wolfe

Kevin P Fahey

Taiji Ema

Kelly Bruland

Ho Wai Lo

Thomas Willoughby Richardson

Richard DeFreez

Gregg Hardy

David Martin Hemenway

Glenn Simenson

Brian C Johansen

William J Jordens

Brady Nilsen

Yasu Osako

Clint R Vandergiessen

Doug J Garcia

Andrew Edwin Hooper

Steve Swaringen

Paul Matthew Lundquist

John Davignon

John D Stackpole

Michael E Fossey

Steve Harris

Feng Chang

Craig D Hutchens

Ed Swenson

Eugenia Tam

Rupendra M Anklekar

A series of laser pulse bundles or bursts are used for micromachining target structures. Each burst includes short laser pulses with temporal pulse widths that are less than approximately 1 nanosecond. A laser micromachining method includes generating a burst of laser pulses and adjusting an envelope of the burst of laser pulses for processing target locations. The method includes adjusting the burst envelope by selectively adjusting one or more first laser pulses within the burst to a first amplitude based on processing characteristics of a first feature at a target location, and selectively adjusting one or more second laser pulses within the burst to a second amplitude based on processing characteristics of a second feature at the target location. The method further includes directing the amplitude adjusted burst of laser pulses to the target location.

Laser micromachining with tailored bursts of short laser pulses

A method of and an apparatus for drilling blind vias with selectable tapers in multilayer electronic circuits permit forming electrical connections between layers while maintaining quality and throughput. The method relies on recognizing that the top diameter of the via and the bottom diameter of the via, which define the taper, are functions of two separate sets of equations. Simultaneous solution of these equations yields a solution space that enables optimization of throughput while maintaining selected taper and quality using temporally unmodified Q-switched COlaser pulses with identical pulse parameters. Real time pulse tailoring is not required; therefore, system complexity and cost may be reduced.

Method of and apparatus for laser drilling holes with improved taper

Systems and methods provide laser pulse equalization at different pulse repetition frequencies (PRFs). After initially pumping a lasing medium from a first pumping level to a peak pumping level, a controller may cause a pump source to continue pumping the lasing medium according to a pulse equalization pumping curve. The equalization pumping curve may be determined based on testing laser pulse parameters at different PRFs to achieve an optimal equalization result of the pulse parameters. The optimization metric used to evaluate various equalization pumping curves may include a consistency of the pulse energy level, peak power level, and/or pulse width of the laser under different PRFs. The equalization pumping curve may be a descending curve from the peak pumping level to the first pumping level. The equalization pumping curve may be a linearly declining curve, a substantially exponentially declining curve, a parametrically declining curve, or any other curve type.

Systems and methods for laser pulse equalization

Processing workpieces such as semiconductor wafers or other materials with a laser includes selecting a target to process that corresponds to a target class associated with a predefined temporal pulse profile. The temporal pulse profile includes a first portion that defines a first time duration, and a second portion that defines a second time duration. A method includes generating a laser pulse based on laser system input parameters configured to shape the laser pulse according to the temporal pulse profile, detecting the generated laser pulse, comparing the generated laser pulse to the temporal pulse profile, and adjusting the laser system input parameters based on the comparison.

Methods and systems for dynamically generating tailored laser pulses

A set () of laser pulses () is employed to sever a conductive link () in a memory or other IC chip. The duration of the set () is preferably shorter than 1,000 ns; and the pulse width of each laser pulse () within the set () is preferably within a range of about 0.1 ps to 30 ns. The set () can be treated as a single 'pulse' by conventional laser positioning systems () to perform on-the-fly link removal without stopping whenever the laser system () fires a set () of laser pulses () at each link (). Conventional IR wavelengths or their harmonics can be employed.

Method for processing a memory link with a set of at least two laser pulses

UV laser cutting throughput through silicon and like materials is improved by dividing a long cut path () into short segments (), from about 10 &#x3bc;m to 1 mm. The laser output () is scanned within a first short segment () for a predetermined number of passes before being moved to and scanned within a second short segment () for a predetermined number of passes. The bite size, segment size (), and segment overlap () can be manipulated to minimize the amount and type of trench backfill. Real-time monitoring is employed to reduce rescanning portions of the cut path(112)where the cut is already completed. Polarization direction of the laser output () is also correlated with the cutting direction to further enhance throughput. This technique can be employed to cut a variety of materials with a variety of different lasers and wavelengths.A multi-step process can optimize the laser processes for each individual layer.

Laser segmented cutting, multi-step cutting, or both

Laser segmented cutting

Dual-beam laser outputs, preferably derived from a single laser beam, improve the quality of the sidewalls of vias drilled in a target material, such as printed circuit board, comprising fiber-reinforced resin. Two embodiments each use two laser output components to remove a portion of target material from a target material location of a workpiece and rapidly clean remnants of the target material bonded to a metal layer underlying the target material location at a material removal rate. A first embodiment entails directing for incidence on a portion of the target material at the target material location a processing laser output having first and second components characterized by respective first and second wavelengths. A second embodiment entails directing for incidence on a portion of the target material at the target material location a processing laser output having first and second components characterized by respective first and pulse widths.

Multiple laser wavelength and pulse width process drilling

An improved method and apparatus for drilling vias in electronic substrates with laser pulses is presented which uses one or more tailored pulses to reduce debris remaining in the via while maintaining system throughput and avoiding damage to the substrate. A tailored pulse is a laser pulse that features a power spike having a peak power 10% higher than the average power of the pulse and lasting less than 50% of the duration of the pulse. Methods and apparatuses for creating tailored pulses by slicing longer duration pulses are shown.

Method and apparatus for laser drilling holes with tailored laser pulses

A solution to an interference effect problem associated with laser processing of target structures entails adjusting laser pulse energy or other laser beam parameter, such as laser pulse temporal shape, based on light reflection information of the target structure and passivation layers stacked across a wafer surface or among multiple wafers in a group of wafers. Laser beam reflection measurements on a target link measurement structure and in a neighboring passivation layer area unoccupied by a link enable calculation of the laser pulse energy adjustment for a more consistent processing result without causing damage to the wafer. For thin film trimming on a wafer, similar reflection measurement information of the laser beam incident on the thin film structure and the passivation layer structure with no thin film present can also deliver the needed information for laser parameter selection to ensure better processing quality.

Laser processing of light reflective multilayer target structure

Processing a memory link with a set of at least two laser pulses

Methods and systems use laser pulses to process a selected structure on or within a semiconductor substrate. The structure has a surface, a width, and a length. The laser pulses propagate along axes that move along a scan beam path relative to the substrate as the laser pulses process the selected structure. The method simultaneously generates on the selected structure first and second laser beam pulses that propagate along respective first and second laser beam axes intersecting the selected structure at distinct first and second locations. The first and second laser beam pulses impinge on the surface of the selected structure respective first and second beam spots. Each beam spot encompasses at least the width of the selected link. The first and second beam spots are spatially offset from one another along the length of the selected structure to define an overlapping region covered by both the first and the second beam spots and a total region covered by one or both of the first and second beam spots. The total region is larger than the first beam spot and also larger than the second beam spot. The method sets respective first and second energy values of the first and second laser beam pulses to cause complete depthwise processing of the selected structure across the width of the structure in at least a portion of the total region.

Semiconductor structure processing using multiple laser beam spots overlapping lengthwise on a structure

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Beaverton, OR, United States of America

Yunlong Sun