MODULE 5:BONDHEAD ASSEMBLY-1

Enabling Objective #1
A. Locate and identify the components of the bond head.
B. Deciribe their funcation.

Bondhead Assembly Overview

Bond Head Component's Function

Be-Al Z Link

• Balance the bond head
• Provides a good foundation for the transducer
• Provides mechanical coupling between dynamic components

Modular Flexure Assembly

• Connects the link and the Z housing assembly
• provides pivot support for the link

Flat Coil Z Motor

• provides vertical motion for the bond head

High Resolution Z Encoder

• Monitors the Z axis position for Z motion control
• Reference mark for extremely replacement axis initialization

DFT 120 Transducer(Dual Frequency Transducer)

• Converts electrical energy to mechanical energy in the form of vibration for bonding process

Point EFO wand

• Delivers a high potential difference between the wire and the EFC wand that creates spark to form a ball at the end of the wire

Parallel wire clamp

• Controls the wire pay-out
• Grasps the wire during the tear operation after second bond
• Provides mechanical coupling between dynamic components

Upper Bumper Stops

• Mechanical upper limit

Lower limit Screw

• Machanical lower limit

Bond Head Controls

Bond Head Control System

• Bond Head Z-axis motion is controlled by a servo system.Motion commands in digital form are passed from CPU1 to CPU2(servo CPU)via the VMEbus
• CPU2 interprets the commands and creats an analog motor drive signal,which is then passed to the z node.
• The z node then puts current through the motor to drive the Bond Head
• Bond head position feedback is returned to Z node from the Z Encoder.
• The amount of Z motor Bond force exerted is proportional to the current in the motor circult,which is monitored by the CPU2 via Enet
• piezo Sensor mounted between the Transducer and Bond Head generates a force signal,which is routed to the piezo Logic Board

• The piezo logic Borad processes and amplifies the signal,where it travels to the Z Node
  -The piezo Logic Board also gets its timing information from the Servo CPU.

  
  

Z-Node Connections

Removal of Bond Head Assembly