J. Phys. IV France 03 (1993) C3-411-C3-417
Comparison of physical and electrical properties of ULPCVD and VLPCVD in situ phosphorus doped polysilicon or undoped polysiliconM. SARRET, A. LIBA, O. BONNAUD, F. LE BIHAN and B. FORTIN
Groupe de Microélectronique et Visualisation, URA 1648 du CNRS, Centre Commun de Microélectronique de l'Ouest, Université de Rennes I, Campus de Beaulieu, 35042 Rennes cedex, France
We have analyzed the physical and electrical properties of Ultra Low Pressure Chemical Vapor Deposition (ULPCVD) and Very Low Pressure Chemical Vapor Deposition (VLPCVD) films of polysilicon. The films are either undoped or in-situ phosphorus doped by varying the phosphine/silane gas mole ratio from 4x10-6 to 4x10-4. For ULPCVD films, pressure is fixed at 10 µbar (1 Pascal) whereas for the VLPCVD ones it is fixed at 100 µbar (10 Pascal). Films are physically and electically characterized. From the analysis of the results it appears that because the deposition rate and the conductivity of ULPCVD films are always lower than the VLPCVD ones, the in-situ phosphorus doped VLPCVD films are potentially better for applications.
© EDP Sciences 1993