This clause explains the support of layerstacks of PCB (Printed
Circuit Boards) in IDA-STEP. A layer stack is composed of a stack of
stratums (some of which are layers) that are of different
kinds of materials and that maybe horizontally structured or
unstructured. The vertical connections between layers are realised
through passages. For both layers and passages
templates/technologies are available, that can be reused as needed.
The functionalities also support building up libraries of different
layer stacks, reusing common objects. The main elements of a
layerstack are: