Al$_2$O$_3$ formation on Si by catalytic chemical vapour deposition

  • Ogita, Yoh-Ichiro (Dept. of Electrical and Electronic Engineering, kanagawa Institute of Technology) ;
  • Shinshi Iehara (Dept. of Electrical and Electronic Engineering, kanagawa Institute of Technology) ;
  • Toshiyuki Tomita (Dept. of Electrical and Electronic Engineering, kanagawa Institute of Technology)
  • Published : 2003.09.01

Abstract

Catalytic chemical vapor deposition (Cat-CVD) has been developed to deposit alumina(Al$_2$O$_3$) thin films on silicon (Si) crystal using N$_2$ bubbled tir-methyl aluminium [Al(CH$_3$)$_3$, TMA] and molecular oxygen (O$_2$) as source species and tungsten wires as a catalyzer. The catalyzer dissociated TMA at approximately 600$^{\circ}C$ The maximum deposition rate was 18 nm/min at a catalyzer temperature of 1000 and substrate temperature of 800$^{\circ}C$. Metal oxide semiconductor (MOS) diodes were fabricated using gates composed of 32.5-nm-thick alumina film deposited as a substrate temperature of 400oC. The capacitance measurements resulted in a relatively dielectric constant of 7, 4, fixed charge density of 1.74*10e12/$\textrm{cm}^2$, small hysteresis voltage of 0.12V, and very few interface trapping charge. The leakage current was 5.01*10e-7 A/$\textrm{cm}^2$ at a gate bias of 1V.

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