Drahtbonden

Drahtbonden, known in English as wire bonding, is a method for creating electrical interconnections between microelectronic devices and their packaging or substrates. It is one of the most widely used interconnect technologies in semiconductor device packaging. In wire bonding, a thin metal wire is attached to conductive pads on the device and on the host substrate using a bonding tool that applies heat, ultrasonic energy, and/or mechanical force.

There are two main bond types: ball bonds, which are formed with a capillary that creates a spherical wire end, and wedge bonds, which use a wedge-shaped tool to make a straight bond. The three primary bonding processes are thermocompression bonding, ultrasonic bonding, and thermosonic bonding (a combination of ultrasonic energy and heat). Wires are typically made of gold or copper, with aluminum used in older generations. Wire diameters commonly range from about 18 to 50 micrometers, depending on device requirements and material.

Equipment for Drahtbonden includes wire bonders, capillaries or wedges, bonding tools or ultrasonic horns, and alignment and vision systems. The process tailors parameters such as bond force, temperature, and ultrasonic power to achieve reliable bonds while controlling loop shape and standoff height. Quality control focuses on bond integrity, loop geometry, and resistance to corrosion and fatigue.

Applications span semiconductor devices, memory modules, sensors, LEDs, and optoelectronic packages. Wire bonding remains a dominant interconnect method for chip-to-package connections, supporting a wide range of consumer electronics, automotive, and industrial applications. Ongoing developments address materials, reliability, and integration with advanced packaging techniques.