Wire Bonding

Wire bonding is used throughout the microelectronics industry as a means of interconnecting chips, substrates, and output pins.

Wedge Bonding Image

Image by TPT

Although flip chip applications are growing, wire bonding continues to produce the vast majority of interconnects, currently responsible for more than 90% of today’s chip interconnects. Wire forms the connections between the bond pad on the IC and the bonding fingers of the leadframe, plastic laminate, or ceramic substrate. Automatic thermosonic gold ball bonding is a high-yield interconnect process that uses heat and ultrasonic energy to form metallurgical bonds. Ultrasonic aluminum wire bonding is also a widely used, high speed, high throughput interconnect process.  Additionally, copper (Cu) wire has long been used as a method of connecting a silicon die to the package terminals. With the recent increase in Gold (Au) wire cost, copper (Cu) wire is an attractive way to manage overall package cost.

Microtek’s wire bonding services provide customers with flexibility and greater latitude in product design. We work closely with you to develop the best solutions for your designs. We can also develop custom solutions to meet your specific needs outside our standard offerings.

Ball Bonding Image

Image by TPT

Microtek performs Gold, Aluminum, or Copper wire bonding services (ball or wedge bonding) as well as ribbon bonding and stud bumping utilizing manual and automatic equipment. Advanced assembly products can be wire bonded, including chip on flex, multiple dies, MEMs devices, etc. Multiple bonding variations can be combined along with encapsulation and glob top options.

Wire diameters range from 0.6 mil (15 µm) to 3.0 mil (76 µm) for gold and copper wire and 1 mil (25 µm) to 10 mil (250 µm) for aluminum wire. We have also produced this Wire Bonding Infographic which highlights some general considerations.






Wire Size Range (µm)




12-51(thick) 51-250(wide)

Min. Recommended Pitch (µm)





Min. Recommended Bond Pads (mils)

2 x 2

3.5 x 3.5

2 x 2

3 x 3

Bonding Type*





Current Carrying Capacity (Amps)

0.29 – 1.83

0.27 – 60

0.29 – 1.83


*BB=ball bond, WB=wedge bond, SB=stitch bond, SSB=standoff stitch bond

Microtek also carries out wire bond pull and ball shear testing. This provides a means of evaluating bond quality and verifying bond consistency and reliability.

In addition to wire bonding services, Microtek can also provide customer solutions for applications in:

  • Die Attach, Die Sorting, Flip-Chip, MEMS, VCSEL, Photonics, Ultrasonic, Thermosonic, RFID, Sensor Assembly, Adhesive Bonding, Eutectic Bonding, etc.