Aluminum Ion Implantation Using a Variable Energy RFQ Implanter

High energy aluminum ion implantation has been studied for power semiconductor device fabrications. A new MeV ion implanter system using a variable energy RFQ linac is developed and tested for pulse mode operation. The RFQ linac is driven by an r.f. resonance circuit having an external variable inductance coil and it is tuned so that the acceleration energy of aluminum ions is 0.9 MeV. The ions are implanted into 6-inch silicon wafers and the depth profile and dose uniformity are measured. Results show that this implanter can be operated stably for more than eight hours, and the depth and dose non-uniformity are 1.35 μm and 0.7 %, respectively. This system is useful for fabrication of semiconductor devices.