A substrate layer structure (100) is adapted to carry electronic device, or components, or electro-mechanical, or electro-chemical sensors, or a combination thereof, and is adapted to be attached to a surface of a human or animal body or biological species. The surface of the flexible substrate layer structure is patterned with a pre-fixed geometry formed by one or more slits (101-701, 502-702). The geometry is selected such that a stretchability of the substrate layer structure becomes adapted to the geometry of the body surface under it.
