Modified E-Gun for Evaporator
Original Publication Date: 1986-Feb-01
Included in the Prior Art Database: 2005-Mar-08
A modification to the gun pocket wall in an evaporator prevents contamination of the Au source by eliminating buildup of the evaporant on the wall. In the evaporator shown in Fig. 1, the turret E-gun is designed with such close tolerances along the rotational plane 1 that, during indexing, a buildup of copper 2 occurs along the gun pocket wall 4. Unless frequent cleaning of the wall takes place, the copper which accumulates can break off and fall into the gold source 3. If this takes place, Cu may be deposited during the gold deposition step in the semiconductor manufacturing operation. This is undesirable since copper oxidation will create high contact resistance, thus damaging wafers. The modified gun pocket wall in Fig. 2 creates a curved surface 5 at the previous flat spot.