GOLD GETTERING INDUCED BY RAPID THERMAL DOPING USING SPIN-ON SOURCES

Transition metals are known to degrade the device performances. Gettering is now widely used to reduce the effects of these contaminants. Rapid thermal processing (RTP) has been shown to advantageously replace conventional long time temperature cycles in various types of applications. Moreover, recent works have evidenced that a gettering of impurities can occur during the RTP cycle. In this letter, we report that RTP diffusion of phosphorus or boron from a spin-on deposited layer can also induce a gettering effect in silicon. For gold-contaminated samples, the redistribution of the Au acceptor level is followed by deep level transient spectroscopy measurements. After a 1000-degrees-C/10 s cycle, gold is depleted in the regions below the surfaces, indicating that gettering has occurred. The mechanism of this RTP-induced gettering is discussed.