MODELING OF LOW-PRESSURE DEPOSITION OF SIO2 BY DECOMPOSITION OF TEOS

The deposition of SiO2 from tetraethylorthosilicate (TEOS) in a hot-wall system at low-pressure conditions has been studied. A two-dimensional model has been developed considering a large number of silicon wafers standing perpendicular to the gas flow. This arrange- ment is preferred in fabrication technology. The model describes the influence of the relevant process parameters on the thickness distribu- tion of deposited oxide across the wafers and from wafer to wafer. The qualitative dependency of calculated profiles on parameter variations agree with experimental results. By choosing suitable parameters oxide layers with thickness deviations as small as 1.6 percent on the wafer and from wafer to wafer have been achieved. Copyright © 1979 by The Institute of Electrical and Electronics Engineers, Inc.