Fabrication Method of Semiconductor Device

Abstract

Provided is a fabrication method of a semiconductor device having an improved production yield.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary cross-sectional view of a semiconductor device according to one embodiment of the present invention during a fabrication step thereof;

FIG. 2 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 1;

FIG. 3 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 2;

FIG. 4 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 3;

FIG. 5 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 4;

FIG. 6 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 5;

FIG. 7 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 6;

FIG. 8 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 7;

FIG. 9 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 8;

FIG. 10 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 9;

FIG. 11 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 10;

FIG. 12 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 11;

FIG. 13 is a fragmentary cross-sectional view of a semiconductor device according to First Comparative Example during a fabrication step thereof;

FIG. 14 is a fragmentary cross-sectional view of the semiconductor device of First Comparative Example during a fabrication step following that of FIG. 13;

FIG. 15 is a fragmentary cross-sectional view of the semiconductor device of First Comparative Example during a fabrication step following that of FIG. 14;

FIG. 16 is a schematic view illustrating a treatment for equalizing the thickness distribution of an insulating film deposited on the main surface of a semiconductor wafer;

FIG. 17 is a schematic view of the control of the moving speed of an etchant nozzle which moves on a semiconductor wafer;

FIG. 18 is a graph showing the deposition thickness distribution of an insulating film when it is deposited on the main surface of a semiconductor wafer;

FIG. 19 is a graph showing the position of an etchant nozzle;

FIG. 20 is a graph showing a change rate of the deposition thickness of an insulating film in a radial direction of the main surface of a semiconductor wafer and a moving speed of an etchant nozzle;

FIG. 21 is a graph showing an etching amount of an insulating film in the treatment for equalizing the thickness distribution of an insulating film deposited on the main surface of a semiconductor wafer;

FIG. 22 is a graph showing the thickness distribution of an insulating film which has been deposited on the main surface of a semiconductor wafer and subjected to the treatment for equalizing the film thickness distribution;

FIG. 23 is a schematic view showing the equation representing an etching time of an insulating film;

FIG. 24 is a fragmentary cross-sectional view of a semiconductor device according to the one embodiment of the present invention during a fabrication step thereof;

FIG. 25 is a fragmentary cross-sectional view of a semiconductor device during a fabrication step following that of FIG. 24;

FIG. 26 is a fragmentary cross-sectional view of a semiconductor device during a fabrication step following that of FIG. 25;

FIG. 27 is a schematic view illustrating the treatment for equalizing the thickness distribution of an insulating film deposited on the main surface of a semiconductor wafer;

FIG. 28 is a graph showing the deposition thickness distribution of an insulating film when it is deposited on the main surface of a semiconductor wafer;

FIG. 29 is a graph showing the position of a rinse solution nozzle;

FIG. 30 is a graph showing a change rate of the deposition thickness of an insulating film in a radial direction of the main surface of a semiconductor wafer and a moving speed of a rinse solution nozzle;

FIG. 31 is a graph showing an etching amount of an insulating film deposited on the main surface of a semiconductor wafer in the treatment for equalizing the thickness distribution of the insulating film;

FIG. 32 is a graph showing the thickness distribution of an insulating film deposited on the main surface of a semiconductor wafer after the treatment for equalizing the film thickness distribution;

FIG. 33 is a schematic view showing the equation representing the etching time of an insulating film;

FIG. 34 is a schematic view illustrating the treatment for equalizing the deposition distribution of an insulating film deposited on the main surface of a semiconductor wafer;

FIG. 35 is a graph showing the deposition thickness distribution of an insulating film when it is deposited on the main surface of a semiconductor wafer;

FIG. 36 is a graph showing the positions of an etchant nozzle and rinse solution nozzle;

FIG. 37 is a graph showing the moving speed of each of an etchant nozzle and rinse solution nozzle;

FIG. 38 is a graph showing the etching amount of an insulating film deposited on the main surface of a semiconductor wafer in the treatment for equalizing the thickness distribution of the insulating film;

FIG. 39 is a graph showing the thickness distribution of an insulating film deposited on the main surface of a semiconductor wafer after the treatment for equalizing the thickness distribution of the insulating film;

FIG. 40 is a fragmentary cross-sectional view of a semiconductor device according to another embodiment of the present invention during a fabrication step thereof;

FIG. 41 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 40;

FIG. 42 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 41;

FIG. 43 is a fragmentary cross-sectional view of a semiconductor device according to Second comparative example during a fabrication step thereof;

FIG. 44 is a fragmentary cross-sectional view of the semiconductor device of Second comparative example during a fabrication step following that of FIG. 43;

FIG. 45 is a graph showing a size of an insulating film pattern at each position of a semiconductor wafer and an effective gate length of a gate electrode formed using the insulating film pattern having the size;

FIG. 46 is a fragmentary cross-sectional view of a semiconductor device according to a further embodiment of the present invention during its manufacturing step;

FIG. 47 is a fragmentary cross-sectional view of the semiconductor device during a fabrication step following that of FIG. 46;

FIG. 48 is a graph showing the etching amount of an insulating film pattern; and

FIG. 49 is a graph showing the size of an insulating film pattern at each position on the main surface of a semiconductor wafer and an effective gate length of a gate electrode formed using the insulating film pattern having the size.

Claims

1. A fabrication method of a semiconductor device, comprising the steps of: (a) preparing a semiconductor wafer;(b) forming a gate electrode over the main surface of the semiconductor wafer;(c) forming a first insulating film over the main surface of the semiconductor wafer so as to cover the gate electrode therewith;(d) after the step (c), correcting the thickness distribution of the first insulating film over the semiconductor wafer; and(e) after the step (d), etching back the first insulating film to form sidewall insulating films made of the first insulating film over the sidewalls of the gate electrode,wherein in the step (d),an etchant for etching the first insulating film is supplied to the main surface of the semiconductor wafer from an etchant supply means while rotating the semiconductor wafer and moving thereabove the etchant supply means from a peripheral side of the main surface of the semiconductor wafer to a central side thereof, andthe moving speed of the etchant supply means is controlled, depending on the thickness distribution of the first insulating film over the semiconductor wafer.

2. A fabrication method of a semiconductor device according to claim 1, wherein in the step (d), the moving speed of the etchant supply means is controlled, depending on a change rate of the thickness of the first insulating film in a radial direction of the semiconductor wafer.

3. A fabrication method of a semiconductor device according to claim 2, wherein in the step (d), the moving speed of the etchant supply means is made lower in a region where the change rate is large than in a region where the change rate is small.

4. A fabrication method of a semiconductor device according to claim 1, wherein in the step (d), the moving speed of the etchant supply means differs between the peripheral side and the central side of the semiconductor wafer.

5. A fabrication method of a semiconductor device according to claim 1, wherein the thickness distribution of the first insulating film formed in the step (c) is large on the peripheral side of the semiconductor wafer and becomes smaller toward the central side of the semiconductor wafer.

6. A fabrication method of a semiconductor device according to claim 1, wherein in the step (d), the etching of the first insulating film is terminated by, after movement of the etchant supply means from the peripheral side to the central side of the main surface of the semiconductor wafer, supplying a rinse solution for terminating the etching of the first insulating film to the main surface of the semiconductor wafer.

7. A fabrication method of a semiconductor device according to claim 6, wherein in the step (d), at each position over the main surface of the semiconductor wafer, the etching of the first insulating film continues from the contact with the etchant supplied from the etchant supply means to the contact with the rinse solution.

8. A fabrication method of a semiconductor device according to claim 6, wherein in the step (d), the etching of the first insulating film is terminated all over the main surface of the semiconductor wafer by supplying the rinse solution to the center of the main surface of the semiconductor wafer.

9. A fabrication method of a semiconductor device according to claim 1, wherein in the step (d),after initiation of the movement of the etchant supply means, a rinse solution for terminating the etching of the first insulating film is supplied from a rinse solution supply means to the main surface of the rotating semiconductor wafer while moving thereabove the rinse solution supply means from the peripheral side to the central side of the main surface of the semiconductor wafer, andthe moving speed of the rinse solution supply means is controlled, depending on the thickness distribution of the first insulating film over the semiconductor wafer.

10. A fabrication method of a semiconductor device according to claim 9, wherein in the step (d), at each position over the main surface of the semiconductor wafer, the etching of the first insulating film continues from the contact with the etchant supplied from the etchant supply means to the contact with the rinse solution supplied from the rinse solution supply means.

11. A fabrication method of a semiconductor device, comprising the steps of: (a) preparing a semiconductor wafer;(b) forming a gate electrode over the main surface of the semiconductor wafer;(c) forming a first insulating film over the main surface of the semiconductor wafer so as to cover the gate electrode therewith;(d) after the step (c), correcting the thickness distribution of the first insulating film over the semiconductor wafer; and(e) after the step (d), etching back the first insulating film to form sidewall insulating films made of the first insulating film over the sidewalls of the gate electrode,wherein in the step (d),after an etchant for etching of the first insulating film is supplied to the main surface of the semiconductor wafer, a rinse solution for terminating the etching of the first insulating film is supplied from a rinse solution supply means to the main surface of the rotating semiconductor wafer while moving thereabove the rinse solution supply means from the peripheral side to the central side over the main surface of the semiconductor wafer, andwherein the moving speed of the rinse solution supply means is controlled, depending on the thickness distribution of the first insulating film over the semiconductor wafer.

12. A fabrication method of a semiconductor device according to claim 11, wherein in the step (d), the moving speed of the rinse solution supply means is controlled, depending on a change rate of the thickness of the first insulating film in a radial direction of the semiconductor wafer.

13. A fabrication method of a semiconductor device according to claim 12, wherein in the step (d), the moving speed of the rinse solution supply means is made lower in a region where the change rate is large than in a region where the change is small.

14. A fabrication method of a semiconductor device according to claim 11, wherein in the step (d), the moving speed of the rinse solution supply means is different between the peripheral side and central side of the semiconductor wafer.

15. A fabrication method of a semiconductor device according to claim 11, wherein the thickness distribution of the first insulating film formed in the step (c) is small on the peripheral side of the semiconductor wafer and becomes larger toward the central side of the semiconductor wafer.

16. A fabrication method of a semiconductor device according to claim 11, wherein in the step (d), the etching of the first insulating film is started all over the main surface of the semiconductor wafer by supplying the etchant to the center of the main surface of the semiconductor wafer.

17. A fabrication method of a semiconductor device according to claim 11, wherein in the step (d), at each position over the main surface of the semiconductor wafer, the etching of the first insulating film continues from the contact with the etchant to the contact with the rinse solution supplied from the rinse supply means.

18. A fabrication method of a semiconductor device, comprising the steps of: (a) preparing a semiconductor wafer;(b) forming a first conductive film for gate electrode over the main surface of the semiconductor wafer;(c) forming a second insulating film for the first conductive film;(d) patterning the second insulating film;(e) after the step (d), correcting the size of the second insulating film pattern over the semiconductor wafer; and(f) after the step (e), etching the first conductive film with the second insulating film pattern as an etching mask to form the gate electrode,wherein in the step (e),an etchant for etching the second insulating film pattern is supplied to the main surface of the semiconductor wafer from an etchant supply means while rotating the semiconductor wafer and moving thereabove the etchant supply means from the peripheral side to the central side of the main surface of the semiconductor wafer, andthe moving speed of the etchant supply means is changed between the peripheral side and central side of the semiconductor wafer.

19. a fabrication method of a semiconductor device according to claim 18, wherein in the step (e), a size of the second insulating film pattern is reduced and a reduction amount of the size of the second insulating film pattern is greater on the peripheral side of the semiconductor wafer than on the central side thereof.

20. A fabrication method of a semiconductor device according to claim 19, wherein in the step (e), the moving speed of the etchant supply means is controlled, depending on the distribution, over the semiconductor wafer, of a taper amount of the gate electrode generated during the step (f).