underfill

underfill

[′ən·dər‚fil]
(metallurgy)
A depression on the face of the weld which falls below the surface of the adjacent base metal.

underfill

A depression, on the face of a weld, which extends below the surface of the adjacent base metal.
References in periodicals archive ?
PIDMSH) will start high-volume manufacturing of molded underfill (MUF) 1 materials for advanced semiconductor packages in March 2018 in response to the increasing demand for these products in China.
Underfill development has also accelerated through the introduction of epoxy-based laminates for package-on-package (PoP), wafer-level chip-scale packages (WLCSP), chipscale packages (CSP) and ball grid array (BGA) devices.
Investigation into the problem revealed that Apple removed the underfill from the controller chips that govern touchscreen functionality.
The SiT1568 also offers an innovative, in-system, auto-calibration feature that allows customers to eliminate timing inaccuracies introduced during system assembly, reflow, underfill, and overmolding.
Underfill was defined as gutta percha more than 2mm short of the radiographic apex.
Underfill is recommended to mitigate the increased risks of mixed alloy soldering of area array packages.
The Spectrum ll he is referring to enables consistent <200pm dots and solder paste line dispensing; features a tilt jetting capability for precision coating and underfill in hard-to-reach places; and offers non-contact laser height sensors for detecting surface heights and allowing tight dispense gaps for thin dispense lines.
Underfill protects solder joints and preventing packages from damage.
It also inspects for epoxy underfill and paste/epoxy squeeze-out and bridging.
If the package has flip chip instead of wire bond, the die attach and wire bond will most likely be replaced by a pick-and-place system for mounting the flip-chip die on the substrate, underfill dispense, and cure system.
123-38A/B-187 is a thermally conductive underfill epoxy that strengthens the chip package and protects it from moisture.
No-flow underfill is a solution for enhancing the drop test performance of CSP solder joints, and has been adopted for portable devices.