J. Phys. IV France 09 (1999) Pr8-885-Pr8-892
Boron doped polysilicon deposition in a sector reactor : Specific phenomena and propertiesE. Scheid1, L. Furgal1 and H. Vergnes2
1 Laboratoire d'Analyse et d'Architecture des Systèmes, UMR 8001 du CNRS, 7 avenue du Colonel Roche, 31077 Toulouse cedex, France
2 Laboratoire Génie Chimique, UMR 5503 du CNRS, 18 chemin de la Loge, 31078 Toulouse cedex, France
In this paper, the advantages of a new LPCVD reactor, called sector reactor, are presented. This reactor is a small scale pilot plant of an annular reactor, designed to solve the problem of uniformity of thickness observed in tubular reactors. This work describes the deposition of in situ Boron doped Silicon from BCl3 and SiH4. The kinetic results shows that the use of the sector reactor allows deposition at temperature as low as 450°C, pressure as high as 6Torr. deposition rates as high as 80nm/mn, keeping the homogeneity of thickness and resistivity at a good level on 10cm substrates. The kinetic and resistivity results are compared to what is obtained in conventional furnace, and are interpreted in terms of gas phase reactions. Finally, the advantage of processing at low temperature (< 555°C) is demonstrated in terms of roughness of thick layers (>0.5µm).
© EDP Sciences 1999