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arXiv · 1511.05436

Polyurethane spray coating of aluminum wire bonds to prevent corrosion and suppress resonant oscillations

Joseph M. Izen·Matthew Kurth·Rusty Boyd
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Abstract

Unencapsulated aluminum wedge wire bonds are common in particle physics pixel and strip detectors. Industry-favored bulk encapsulation is eschewed due to the range of operating temperatures and radiation. Wire bond failures are a persistent source of tracking-detector failure. Unencapsulated bonds are vulnerable to condensation-induced corrosion, particularly when halides are present. Oscillations from periodic Lorentz forces are documented as another source of wire bond failure. Spray application of polyurethane coatings, performance of polyurethane-coated wire bonds after climate chamber exposure, and resonant properties of polyurethane-coated wire bonds and their resistance to periodic Lorentz forces are under study for use in a future High Luminosity Large Hadron Collider detector such as the ATLAS Inner Tracker upgrade.

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Joseph M. Izen, Matthew Kurth, Rusty Boyd. 2016-01-04. Polyurethane spray coating of aluminum wire bonds to prevent corrosion and suppress resonant oscillations. https://doi.org/10.1088/1748-0221%2F11%2F03%2Fc03019

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