Connector element and method of bonding such connector element to a substrate

A connector element for being bonded to a substrate by pressing the connector element and the substrate together and mechanically exciting the connector element and the substrate relative to each other when being pressed together, comprising:

• a base portion having a distal surface;
• a plurality of protrusions distally extending from the distal surface of the base portion, wherein the plurality of protrusions comprise a thermoplastic material configured to liquefy when the connector element is pressed to the substrate and mechanically excited;
• link members comprising a thermoplastic material configured to liquefy when the connector element is pressed to the substrate and mechanically excited, wherein each link member connects two neighboring protrusions of the plurality of protrusions;
• and
• a central dome distally extending from the distal surface of the base portion, wherein the central dome portion is surrounded by the plurality of protrusions.