Process margins for pulsed laser-induced via filling

Journal Article · Thu Nov 01 00:00:00 EST 1990 · Journal of Vacuum Science and Technology, B: Microelectronics Processing and Phenomena; (USA)

DOI:https://doi.org/10.1116/1.585158· OSTI ID:6228374

Marella, P F; Tuckerman, D B; Pease, R F ^[1]

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1. Solid-State Electronics Laboratory, Stanford University, Stanford, CA 94305 (USA) LP Program, Special Studies Division, Lawrence Livermore National Laboratory, Livermore, CA 94550

Process margins have been experimentally determined for pulsed laser-induced filling of Au-coated square vias of varying size (2--15 {mu}m side lengths) and aspect ratio using either a flashlamp-pumped dye laser ({lambda}=490 nm, FWHM pulse duration=600 ns) or an excimer laser (Xe*Cl, {lambda}=308 nm, FWHM pulse duration=35 ns). For 2.0-{mu}m-thick Au coatings, either laser provided comparable process margins (up to {plus minus}14%) for the same via diameter. For 3.8-{mu}m-thick coatings, the flashlamp-pumped dye laser exhibited process margins (up to {plus minus}21%) nearly twice that of the excimer laser ({plus minus}12% maximum). Near the damage threshold fluence, excimer laser-induced film damage was localized near irradiated spot edges (the regions of highest intensity gradient), suggesting evaporative recoil effects due to the high peak intensity of this laser. In contrast, the longer, less intense pulse generated by the flashlamp-pumped dye laser did not give rise to these localized effects, instead producing film damage in the regions of highest incident intensity (the damage mechanism has not been identified). Frozen-in capillary waves, produced during the laser-induced flow of the molten metal, are shown to yield information about the metal's melt duration while suggesting a method for constructing an {ital in}-{ital situ} process monitor.

• OSTI ID: 6228374
• Journal Information: Journal of Vacuum Science and Technology, B: Microelectronics Processing and Phenomena; (USA), Vol. 8:6; ISSN 0734-211X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GOLD
PHYSICAL RADIATION EFFECTS
INTEGRATED CIRCUITS
CONNECTORS
DYE LASERS
EXCIMER LASERS
FILMS
LASER RADIATION
MELTING
CONDUCTOR DEVICES
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
ELECTRONIC CIRCUITS
ELEMENTS
EQUIPMENT
GAS LASERS
LASERS
LIQUID LASERS
METALS
MICROELECTRONIC CIRCUITS
PHASE TRANSFORMATIONS
RADIATION EFFECTS
RADIATIONS
TRANSITION ELEMENTS
360106* - Metals & Alloys- Radiation Effects