An electronic assembly includes a substrate having bond pads on a surface of the substrate. A solder mask covers the surface of the substrate, and a solder connection is disposed on each of the bond pads. At least one trench is formed in the solder mask, and is located between adjacent ones of the bond pads. At least one component has contact pads, and each contact pad is connected to one of the bond pads via one of the solder connections. The trench is located beneath the device and extends at least from one edge of the device to a location underneath the device. Underfill material fills the trench and space between the solder mask and the device.