An integrated circuit package includes a core such as a thin glass core with through-core vias. A photo-patternable material is disposed directly on surfaces of the core and in the through-core vias and is selectively patterned to expose at least an exposed portion of the surface of the core and the through-core vias. A metal layer, such as copper, is disposed in the exposed portion of the core and in the through-core vias. A mechanical handler frame may be used to clamp together the various layers including the core and the photo-patternable material. The photo-patternable material that remains after patterning is permanent, and prevents the mechanical handler frame from directly contacting the core. Thus the photo-patternable material provides mechanical support to the core and protects the core from the mechanical handler.