Heated Stage for Thermosonic Wedge Bonding

Step 2 Machining the block

The block forms the heated surface and provides thermal mass for the thermal feedback system. I chose to go with a 3x2x1 inch block because its big enough for most of my work, and small enough to fit easily on the wire bonder's work surface.

I machined the block square on a milling machine and bored a 1/2 inch hole in one edge, and 4 holes for standoffs on the corners. I used a 0.257 inch reamer for finishing the standoff holes which improves the inner surface finish.

Another feature I decided to include was a trough around the perimeter of the block in order to use tiny C-clamps to hold down a workpiece to the stage. This was accomplished again on the milling machine using a 1/8 inch end mill.