Best-practice methods for PCB via fabrication are as varied as the definition of the microvia. All things considered, the best practice is to

While there is no set definition for microvia, the industry primarily considers these to be drilled holes with diameters of 0.012” or less.
Moreover, there are three primary subsets of this term in PCB designs:
Through via
Traverses from top layer to bottom layer
Blind via
Starts at outer layer and ends at inner one
Buried via
Begins and ends at inner layers only (not visible from exterior)
Because they use very similar mechanical drilling processes, through and buried vias are simpler to fabricate as they utilize mechanical drilling.
Traverses from top layer to bottom layer
Blind via
Starts at outer layer and ends at inner one
Buried via
Begins and ends at inner layers only (not visible from exterior)
Because they use very similar mechanical drilling processes, through and buried vias are simpler to fabricate as they utilize mechanical drilling.
Microvia Circuit Boards