1. WIRE BONDING
Group 2: Tống Văn Khoa
Cao Văn Phước
Trần Phúc Thành

2. Why Wire Bonding?
 Enable an IC to be electrically interconnected
to the package, and to allow that IC to be
handled, tested and “burnt-in”
 Such “qualified” IC used in electronic
product.
 Interconnected to other ICs, passives, flat
panel displays, keyboards, sensors,
connectors, antennas, switches, etc.
 PRIMARY purpose – enable ICs to be
interconnected with rest of the system.
 Primary functions of IC assembly:
(1) To provide signal and power distribution of
the packaged IC to the system. Another way to bonding: Tape
automated bonding (TAB)
(2) To provide mechanical support to fragile IC Flip chip
(3) To provide environmental protection of the
IC

3. Introduction
 Used in interconnecting the Die to various substrates
 … The most popular interconnection method
 Wire bonding is a SOLID phase welding process where the
two metallic materials, a thin wire and the metallization on
Pad surface are brought into intimate contact under a
combination of heat, pressure, and/or ultrasonic energy…..

4. Types of Wire Bonding
 Wire bonding is made using two types of tools:
 A Wedge- Called Wedge bonding
 B: Capillary- Called ball bonding
 Very inexpensive- A penny per pin

5. Bonding Tools

6. Ball Bonding
 Process Steps
 Capillary loaded with Au wire
 EFO wand generates a spark to melt the Au wire at the
tip
 Apply pressure and ultrasonic energy, heat to form ball
bond at bond pad on chip side
 Bonding on substrate pad
 Loop formation
 Package bond pad formation by stitch bonding
 Wire break-off to finish process

10. Wedge Bonding

11. Al Is More Suitable For Wedge
Bonding

12.  Process Steps
 Wedge tool loaded
with wire
 Apply pressure and
ultrasonic energy to
form wedge
 Bonding on substrate
pad
 Loop formation
 Package bond pad
formation
 Wire break-off to
finish process

14. Features of Wire Bonding Method
 High speed( Bonding time 40ms: 2-4 wires/ sec)
 Economical
 Strong bond
 Larger Bonding pad (0,2mm gold wire: 0,5*0,5 mm
pad)
 Ultrasonic can be used

15. (Dis)advantages
 The advantages of wirebonding:
 Highly flexible chip-to-package interconnection process
 Low defect rates or high yield interconnection processing
 Easily programmed
 High reliability interconnection structure
 Very large industry infrastructure supporting the technology
 Rapid advances in equipment, tools, and material technology
 The disadvantages of wirebonding:
 Slower interconnection rates due to point-to-point processing
of each wirebond
 Long chip-to-package interconnection lengths, degrading
electrical performance
 Larger footprint required for chip to package interconnection

16. Summary
 Function of Wire Bonding
 Types of Wire Bonding
 Ball Bonding
 Wedge Bonding
 Advantages and Disadvantages

17. References
 Wikipedia
 http://en.wikipedia.org/wiki/Wire_bonding
 http://en.wikipedia.org/wiki/Ball_bonding
 Youtube
 http://r1---sn-o097zuel.c.youtube.com/videoplayback

18. THANK YOU FOR LISTENING !
Nano- Electronic
Materials
Group-HUST