Gold and Aluminum Bond Wire Properties Ultrasonic &
Wedge Bonding
Gold wire bonding is a popular technique in the integrated circuit (IC) industry
due to its reliability, durability, and low resistance. The technique is commonly
used to create interconnects between components such as transistors, capacitors,
and resistors, as well as to connect ICs to their packaging. See table of
bonding wire properties below.
Thermosonic Wire Bonding is a process used in the manufacturing
of integrated circuits (ICs) to create interconnections between the different components
of the IC. This technique involves the use of heat and ultrasonic vibrations to
bond a thin wire made of gold or aluminum to the components of the IC.
The process of thermosonic wire bonding typically involves several steps. First,
a thin wire is fed through a machine that guides it to the correct location on the
IC. The wire is then heated using a combination of high-frequency ultrasonic vibrations
and thermal energy, which softens the wire and causes it to bond to the components
of the IC.
One of the advantages of thermosonic wire bonding is that it can create very
strong and reliable bonds between the wire and the components of the IC. This is
because the ultrasonic vibrations used in the bonding process help to break down
any oxides or contaminants on the surface of the components, allowing the wire to
form a strong bond.
In addition, thermosonic wire bonding can be used with a wide range of materials,
making it a versatile bonding technique for IC manufacturers. The technique can
also be used to create interconnects between components with very small feature
sizes, which is important for high-density ICs.
However, like all bonding techniques, thermosonic wire bonding does have some
limitations. For example, the process can be time-consuming, as each wire must be
bonded individually. In addition, the heat and ultrasonic energy used in the bonding
process can potentially damage the components of the IC if not carefully controlled.
Wedge Wire Bonding is a process used in the manufacturing of
integrated circuits (ICs) to create interconnections between the different components
of the IC. This technique involves the use of a wedge-shaped tool to bond a thin
wire made of gold or aluminum to the components of the IC.
The process of wedge wire bonding typically involves several steps. First, a
thin wire is fed through a machine that creates a wedge-shaped tool. The tool is
then brought into contact with the components of the IC, and pressure is applied
to bond the wire to the components.
One of the advantages of wedge wire bonding is that it can create strong and
reliable bonds between the wire and the components of the IC. This is because the
wedge-shaped tool allows for precise control of the bonding force and placement
of the wire.
In addition, wedge wire bonding can be used with a wide range of materials, making
it a versatile bonding technique for IC manufacturers. The technique can also be
used to create interconnects between components with very small feature sizes, which
is important for high-density ICs.
However, like all bonding techniques, wedge wire bonding does have some limitations.
For example, it can be more difficult to control the quality of the bonds with this
technique compared to other bonding techniques such as thermosonic bonding. In addition,
the size and shape of the wedge tool can limit the accessibility to certain components,
especially in complex IC designs.
Here is an article which gives equations for calculating fusing current when
the duty cycle is very small, "Bond Wire Fusing in ICs with Pulsed Current." Note that much larger
currents can be handled with very short pulses. Here is the
whitepaper for the
formula.