Transcript thermocompression

THERMOCOMPRESSION
Introduction :
•Thermocompression bonding : utilizes high
temperature and high impact force, and the
ball/wedge method. No ultrasonic is used
during bonding. Use in special application
such as bonding of GaAs devices
•The joining together of two materials,
without an intermediate material, by the
application of pressure and heat in the
absence of an electrical current.
Ball\Wedge : The machine used
to make ball/wedge bonds
incorporates a 'flame-off' arm. At
the end of each full bonding
cycle an arc is struck between
the arm and the end of the wire,
producing a ball. The ball is
deformed as it is welded to the
IC (integrated circuit), the
second bond (known as the
wedge, capillary-wedge,
termination bond or stitch bond)
is then made to the substrate.
The figure below shows a
schematic representation of the
geometry of a ball/wedge bond.
Wirebonding
Pressur
e
Temperature
Ultrasonic
energy
Wire
Pad
Thermocompressio
n
High
300-500 oC
No
Au,
Al, Au
Ultrasonic
Low
25 oC
Yes
Au, Al
Al, Au
Thermosonic
Low
100-150 oC
Yes
Au
Al, Au
Table I
Thermocompression bonding, the innovation under consideration,
involves heating the semiconductor surface to about 200_C to 300_C
and then simply pressing the wire to be bonded against the
semiconductor chip surface at the appropriate place with a pressure
from 5,000 to 10,000 lb/sq in. In a few seconds a bondwith excellent
physical and electrical properties is formed. The machine that
performs this task is called a thermocompression bonder.
Group Members :
-Mohd Amirull Ameer
-Mazlini Bt Abdullah
-Harold Fred Loduin
-Mohd Rahmat
-Zul Wang Gani
Thermocompression Bonding
Thermocompression bonding is used for bonding gold
wire with heat, pressure and time. No ultrasonic energy
is applied to the bond wire. This bonding process
requires elevated temperatures during the bonding
process when compared to "thermosonic bonding". The
heat is supplied by a heated workholder, which holds the
part being bonded. The bonding wedge is usually heated
as well. The bonding machine supplies the pressure as it
pushes down the wedge onto the wire. The time or
duration is how long the bonding wedge sits on the wire.
Step Of Thermocompression :