BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a configuration diagram of an etching apparatus according to embodiment 1 of the present invention;
FIG. 2 shows a structure of a gas supply unit of the etching apparatus according to embodiment 1;
FIG. 3 shows a plasma discharge stable range when the ratio of power is 1:1 according to embodiment 1;
FIG. 4 shows a plasma discharge stable range when the ratio of power is 1:0 according to embodiment 1;
FIG. 5 shows a plasma discharge stable range when the ratio of power is 0:1 according to embodiment 1;
FIG. 6 is an etching condition chart according to embodiment 2 of the present invention;
FIG. 7 shows a time variation of the total gas flow rate of the first wafer according to embodiment 1;
FIG. 8 shows a time variation of the total gas flow rate of the second wafer according to embodiment 1;
FIG. 9 shows the structure of a gas supply unit of the etching apparatus according to embodiment 2;
FIG. 10 shows a time variation of the total gas flow rate of the first wafer according to embodiment 2;
FIG. 11 shows a time variation of the total gas flow rate of the second wafer according to embodiment 2;
FIG. 12 shows a time variation of the reflecting power of embodiment 2;
FIG. 13 shows a time variation of the vacuum processing chamber pressure of embodiment 2;
FIG. 14 is a configuration diagram of the etching apparatus according to embodiment 3 of the present invention;
FIG. 15 shows a time variation of reflection intensity obtained via an interference film thickness monitor according to embodiment 3;
FIG. 16 shows a time variation of the total gas flow rate according to embodiment 3;
FIG. 17 shows a time variation of the vacuum processing chamber pressure according to embodiment 3;
FIG. 18 shows a time variation of the reflecting power according to the present invention;
FIG. 19 shows a time variation of the total gas flow rate according to embodiment 3 of the present invention;
FIG. 20 shows a time variation of the vacuum processing chamber pressure according to embodiment 3;
FIG. 21 shows a time variation of the reflecting power according to embodiment 3;
FIG. 22 shows a time variation of the vacuum processing chamber pressure according to embodiment 3;
FIG. 23 is a configuration diagram of the etching apparatus according to embodiment 4 of the present invention;
FIG. 24 shows the relationship between a valve opening control cycle and a pressure minimal value according to embodiment 4;
FIG. 25 shows a time variation of the vacuum processing chamber pressure according to embodiment 4;
FIG. 26 shows a time variation of the reflecting power according to embodiment 4;
FIG. 27 is a configuration diagram of the etching apparatus according to embodiment 5 of the present invention;
FIG. 28 is an etching condition chart according to embodiment 5;
FIG. 29 is a cross-sectional structure of the substrate to be etched prior to processing according to embodiment 5;
FIG. 30 is a cross-sectional structure of the substrate to be etched immediately subsequent to step 2 according to embodiment 5;
FIG. 31 is a cross-sectional structure of the substrate to be etched immediately subsequent to step 3 according to embodiment 5;
FIG. 32 shows a time variation of the vacuum processing chamber pressure in the case of intermittent discharge;
FIG. 33 shows a time variation of the input reflecting power of microwaves in the case of intermittent discharge;
FIG. 34 shows a time variation of vacuum processing chamber pressure in the case of continuous discharge;
FIG. 35 shows a time variation of the input reflecting power of microwaves in the case of continuous discharge;
FIG. 36 shows the relationship between the vacuum processing chamber pressure and the etching rate of silicon and silicon oxide film according to the condition of step 3;
FIG. 37 shows a time variation of the total gas flow rate according to embodiment 6 of the present invention;
FIG. 38 shows a time variation of the total gas flow rate according to embodiment 6;
FIG. 39 is a time variation of the vacuum processing chamber pressure according to embodiment 6;
FIG. 40 is a cross-sectional structure of the substrate to be etched immediately subsequent to step 3 according to embodiment 6; and
FIG. 41 shows a structure of a gas supply unit according to the prior art example of patent document 1.