| 摘要 |
PURPOSE:To obtain an electrically stable PSG film covering a stepped section satisfactorily by exciting and activating PH3 gas more than other gas wherein the bonding with P and O2 is attempted. CONSTITUTION:A suspector 6 is installed in a bell jar 5 and a wafer 4 is placed on the susceptor 6 for heating by a heater 7. SiH4 and N2O are poured from a pipe- shaped shower 8. A high-frequency voltage is applied across the shower 8 and the susceptor 6 and plasma is excited to activate SiH4, N2O or the like. A high-frequency current flows into coils 11 at the upper part of the jar 5 to excite the plasma and induced 10 PH3 is activated. Furthermore, the PH3 again passes through a plasma region at the upper part of the wafer 4 and the PH3 is completely activated. As a result, the sufficient bonding with P and O2 follows to produce SiO2.P2O5. This film satisfactorily covers a stepped section and has low dielectric constant. Chemical resistance will also be improved by maintaining the P concentration of the surface layer at 1mol in percent or below. |
