A Study on the Self-Aligned Cobalt Silicidation and the Formation of a Shallow Junction by Concurrent Junction Process

동시 접합 공정에 의한 자기정렬 코발트 실리사이트 및 얇은 접합 형성에 관한 연구

  • 이석운 (서울대학교 금속공학과) ;
  • 민경익 (서울대학교 금속공학과) ;
  • 주승기 (서울대학교 금속공학과)
  • Published : 1992.02.01

Abstract

Concurrent Junction process (simultaneous formation of a silicide and a junction on the implanted substrate) by Rapid Thermal Annealig has been investigated. Electrical and material properties of CoSi$_2$ films were analyzed with Alpha Step, 4-point probe, X-ray diffraction(XRD) and Scanning Electron Microscope(SEM). And CoSi$_2$ junctions were examined with Spreading Resistance probe in order to see the redistribution of electrically activated dopants and determined the junction depth. Two step annealing process, which was 80$0^{\circ}C$ for 30sec and 100$0^{\circ}C$ for 30sec in NS12T ambient was employed to form CoSi$_2$ and shallow junctions. Resistivity of CoSi$_2$ was turned out to be 11-15${\mu}$cm and shallow junctions less than 0.1$\mu$m were successfully formed by the process. It was found that the dopant concentration at CoSi$_2$/Si interface increased as decreasing the thickness of Co films in case of $p^{+}/n$ and $n^{+}/p$ junctions while the junction depth decreased as increasing CoSiS12T thickness in case of $p^{+}/n$ junction.

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