Ion Implant Heat Transfer
Original Publication Date: 1979-Apr-01
Included in the Prior Art Database: 2005-Feb-20
During a typical ion implant process, considerable power is delivered to the semiconductor wafer, causing its temperature to rise. For example, a 3-minute 15-watt implant causes the wafer (2.25 inches) to rise to 320 degrees C. The temperature rise is often detrimental to the processing. The following examples illustrate some of these detrimental effects: (1) Excessive heating of samples with photoresist masking causes outgassing and consequent dosimetry inaccuracy due to pressure increases. In addition, the photoresist may flow, causing the pattern to change. (2) For implantation gettering, excessive heating causes annealing of the damage centers which reduces the effectiveness. (3) Implants at elevated temperatures can result in impurity redistribution and annealing effects which may be undesirable.