Wire Bonder

From LNF Wiki
Jump to navigation Jump to search
Wire Bonder
Equipment Details
Technology Packaging
Materials Restriction Undefined
Equipment Manual
Overview System overview
Operating Procedure SOP
Supported Processes Supported processes
User Processes User Processes
Maintenance Maintenance

The K&S 4123 Wire Bonder is a wedge bonder that is designed to connect bond pads on devices to the leads of a package such as DIP or TO-5 cases. It can also be used to interconnect bond pads between two devices, the same device or to a printed circuit board.



Several bond modes are available.

  • Thermocompression Bonding: Only heat and pressure are used to perform bonds. This works best with gold wire.
  • Ultrasonic Bonding: Pressure and ultrasonic energy are used to perform bonds.
  • Thermosonic Bonding: Both heat and ultrasonic energy with pressure are used to perform bonds.

Two modes of operation are available.

  • Chessman mode (semi automatic)
    • Bonding heights (1st search, loop and 2nd search) are preset using controls on the panel. This allows rapid bonding of pads that are the same height.
  • Manual Z mode
    • Bonding heights are achieved with the manual Z lever. This allows for a wide range of bond pad heights.

System overview

Hardware details

Four types of wire are available at the LNF.

  • Aluminum: .7 mil (17.78 μm) diameter.
  • Aluminum: 1 mil (25.4 μm) diameter.
  • Gold: .7 mil (17.78 μm) diameter.
  • Gold: 1 mil (25.4 μm) diameter.

Tool features

  • Bonding area: 3.75" x 3.75" (95 mm x 95 mm).
  • Workholder sample size (max): Approximately 2.25" (57mm) square or 2.25" (57mm) diameter wafers.
  • Workholder temperature controller.
  • Wedge heater.
  • Chessman ratio: 6:1.
  • Cycle time: 850 ms (incl. 100 ms bond time).
  • Bond force: 10 to 160 gr.
  • Bond time: 10 to 100 ms.
  • Ultrasonic power: Low 1.3 W. max., High 2.0 W. max.

Substrate or package requirements

  • Wafer or Package Size
    • A heated workholder is available capable of holding up to approximately 2.25" (57mm) square or 2.25" (57mm) diameter wafers. It can also hold most DIP packages with .1" lead spacing.
    • A heated workholder is available capable holding two TO-5 packages.
  • Wafer thickness
    • The device or package must be thin enough to fit under the workholder clamps.
  • Bond Pads
    • Bond pads should be at least 75 µm square to make is easier to place the bond. Larger pads are better. Bond size should not exceed 75% of the bond pad size.
    • Gold or Aluminum pads provide the most reliable bonds. Platinum and Copper can also be bonded.
    • Metal adhesion must be good to prevent lifting of the pad metal at the bond point.
    • Thicker metal will allow for more reliable bonding.
    • A minimum of 0.76 micron of soft gold on an interface material such as 5 micron nickel works well for bondability and to minimize pad damage. Thicker is better. There has been limited success with thinner layers.
    • For aluminum, .8 micron pad thickness is recommended, 3 micron for higher reliability.
    • All metal surfaces must be clean. There may not be any contamination such as oils, glue or corrosion.
  • The device to be bonded must be mounted on a solid surface using a hard material. For example, mounting with soft tape will reduce the effectiveness of the ultrasonic energy. If the device is large enough to be placed directly on the workholder, no special mounting is necessary. Use both workholder clamps to ensure that the entire device/package is in contact with the workholder surface.

Material restrictions

These materials have been bonded successfully on the LNF Wire bonder.

  • Aluminum
  • Copper
  • Gold
  • Platinum

Supported processes

Wire bonding is commonly made to Aluminum and Gold bond pads. We have Gold and Aluminum wire. Other materials require special consideration. Some of the materials that have been bonded on this tool are described in more detail on the Processes page.

Standard operating procedure

Widget text will go here.

Checkout procedure

  1. Read through this page and the Standard Operating Procedure above.
  2. Create a Helpdesk Ticket requesting training.
  3. A tool engineer will schedule a time for initial training.
  4. You may practice with your mentor or another authorized user until you are comfortable with tool operation.
  5. Schedule a checkout session with a tool engineer via the helpdesk ticket system. If this checkout is successful, the engineer will authorize you on the tool.


All tool maintenance is performed by LNF Staff.
Maintenance procedures

Further reading