Low energy implant throughput improvement by using the Arsenic dimer ion (As2+) on the Axcelis GSDIII/LED ion implanter

Abstract

Low energy arsenic implants used in the formation of ultra-shallow junctions are characterized on the GSD/Ultra high current ion implanter. Significant advantages in beam current and process throughput are demonstrated by using the Arsenic dimer ion (As₂⁺) for implant energies lower than 5 keV. Dimer implants require only half the dose and use twice the energy of equivalent As implants, resulting in significantly reduced implant times. Process results including Thermawave (TW), sheet resistance (R_s) and SIMS profiles show equivalence between As⁺ and As₂⁺ implants.