Engineering ultra-shallow junctions using fRTP™

This paper discusses engineering of ultra-shallow junctions using a new annealing technique called Flash-assist RTP(TM) (fRTP). This technique offers effective process times in the 1-10ms range, which fills the gap between traditional RTP and laser thermal processing. A discussion on the evolution of RTP based on the thermal response time of the heat source and wafer is presented. Technical innovations required for fRTP are discussed including why an extremely powerful flash lamp is essential for this application. Comparisons of the various annealing techniques are made and results presented to show the impact on junction depth, abruptness and resistivity. It is shown that a process engineer can more or less independently control diffusion and activation over a wide range enabling the formation of junctions meeting future requirements of the ITRS.