The Drill-Pair Properties dialog provides controls to configure a drill pair for the active layer stack in terms of start and stop layers. Drill pairs must be configured when blind, buried, or build-up type vias are to be used, with a drill pair for each layer-pair that a via spans. The dialog is also used for defining back drill start stop layers for a design that uses back drilling.
Select a currently-defined drill pair (other than the Top Layer - Bottom Layer drill pair when the active stack is the default Board Layer Stack, which cannot be edited) then click the Drill Pair Properties button.
The Drill-Pair Manager dialog is accessed by clicking the Drill Pairs button in the Layer Stack Manager dialog. The latter is accessed by clicking Design » Layer Stack Manager from the main menus.
Drill-Pair Properties - the following fields collectively define the drill pair:
Start Layer - the start layer for the pair. Choose from any of the currently defined signal and plane layers for the board as configured and enabled in the active layer stackup.
Stop Layer - the stop layer for the pair. Choose from any of the currently defined signal and plane layers for the board as configured and enabled in the active layer stackup.
Back drill pair - enable this option to define this pairing of start and stop layers as the layers that will potentially be back-drilled through. One of the Start/Stop layers must be a surface layer (Top Layer or Bottom Layer); the other layer can be any internal layer. To learn more about back drilling, refer to the Controlled Depth Drilling, or Back Drilling article.
Drill pairs must be defined to suit the layer stack-up style. This should be done in consultation with your board manufacturer to ensure that your design matches their fabrication technology.