Substrates with spacers, including substrates with solder resist spacers, and associated devices, systems, and methods

A system, comprising:

• a substrate, a first electronic device mounted on a first surface of the substrate, and a second electronic device and third electronic device that are each mounted on the first electronic device,
• wherein the substrate includes
• a solder resist layer disposed over at least a portion of the first surface,
• a plurality of electrical contacts at the first surface of the substrate and electrically coupled to corresponding electrical contacts at a first surface of the first electronic device,
• a first solder resist spacer disposed on the solder resist layer at a first location laterally offset from a first side of the first electronic device, wherein the first solder resist spacer has a height corresponding to a thickness of the first electronic device, and wherein the first solder resist spacer is configured as a dam to limit bleed out of underfill laterally away from the plurality of electrical contacts along the first surface of the substrate and toward the first solder resist spacer, and
• a second solder resist spacer disposed on the solder resist layer at second location laterally offset from a second side of the first electronic device opposite the first side such that the first and second solder resist spacers flank the first electronic device, wherein the second solder resist spacer has a height corresponding to the thickness of the first electronic device, and wherein the second solder resist spacer is configured as a dam to limit bleed out of underfill laterally away from the plurality of electrical contacts along the first surface of the substrate and toward the second solder resist spacer,
• wherein the second electronic device is further mounted on the first solder resist spacer without being mounted on the second solder resist spacer, and
• wherein the third electronic device is further mounted on the second solder resist spacer without being mounted on the first solder resist spacer.

A method of manufacturing a system comprising a substrate, a first electronic device, and a second electronic device, the method comprising:

• disposing a solder resist spacer on a solder resist layer of the substrate, the solder resist layer disposed over at least a portion of a first surface of the substrate;
• mounting the first electronic device in an opening of the solder resist layer and on the first surface of the substrate such that first electrical contacts at a first surface of the first electronic device are electrically coupled to second electrical contacts at the first surface of the substrate at a location along the first surface of the substrate laterally spaced apart from the solder resist spacer;
• dispensing underfill such that (a) at least a portion of the underfill is positioned (i) between the first electronic device and the first surface of the substrate and (ii) about at least some electrical connections formed between the first and second electrical contacts, and (b) bleed out of the underfill in a direction laterally away from the first electronic device along the first surface of the substrate is limited by a face of the solder resist spacer directed toward the first electronic device;
• and
• mounting the second electronic device on the solder resist spacer and the first electronic device such that a first side of the second electronic device is vertically aligned with the first electronic device and a second side of the second electronic device opposite the first side is not vertically aligned with the first electronic device.