Regarding the issue of drilling through holes on solder pads

1. It is not impossible to drill holes on the solder pad. If you are willing to spend money on small holes, the laser hole and plugging process should be fine;
a. For BGA pads with a spacing of less than or equal to 0.5mm, they must be very dense and holes must be drilled on the pads; The difficulty and cost of PCB plate making process have increased;
b. For some QFN and other packaged central pads and grounding pads, it is necessary to drill, and the through-hole should not be too large. Reflux and peaks are allowed;
c. In RF applications, it is common to have through holes on the solder pads of devices such as resistors and capacitors;
d. It is common to place through holes on the solder pads of some high-speed devices.

2. In general, manual soldering is not a problem, and reflow soldering should not be used. After the solder flows into the hole, there is too little solder on the solder pad, which can easily cause virtual soldering;
For small resistive and capacitive components, it may cause one end to tilt up, commonly known as the phenomenon of vertical monuments.