Bonding technology in micro-electronics, usually micro-welding technology. In wire bonding, the connections between semiconductor chips and the circuit substrates are made by wires which are welded to the contact islands on the chip or on the pad of the wiring substrate or the connection comb. The welded connection is generated by temperature and pressure (thermal compression bonding) or friction (ultrasonic bonding). In a broader sense, other micro-contact processes such as micro-soldering, micro-adhesive bonding, and die bonding are also referred to as bonding. In adhesive bonding, conductive adhesives generate the connection. In printed circuit board technology, bonding processes are becoming more and more important in the processing of uncapped chips, e.g. in the chip-on-board (COB) technology. In anodic bonding, even surfaces are sealed through electric fields.