Do EPC GaN eFETs pads come pretinted with solder?

Designing with GaN FETs and ICs Assembly and Layout
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1

In the video: https://www.youtube.com/watch?v=Dz8uRmQKDAM
No mention is made about solder paste . Flux is just applied to the pads before the eFET is mounted and heated. Do EPC GaN eFETs pads come pretinted with solder? What am I missing?

2

Yes, the EPC eGaN FETs come with solder balls or solder bars. They don’t sit flat on a board like a packaged part, these chip-scale FETs are meant to have a gap between the body of the FET and the board. That allows the solder connection to flex a bit, which is very good for reliability (thermal cycling).
For automated assembly, solder paste is applied to the pads, with a laser-cut stencil.
For manual assembly, there are a few ways to do it.
• The video shows only flux added to the board, as you noticed.
• Another way is to apply solder paste. The application note Assembling eGaN FETs and ICs also gives the option of a reflow oven (as well as a hot air gun)