Browse Prior Art Database

Radial Etch Control Boat

IP.com Disclosure Number: IPCOM000048601D
Original Publication Date: 1982-Feb-01
Included in the Prior Art Database: 2005-Feb-08
Document File: 3 page(s) / 74K

Publishing Venue

IBM

Related People

Ryan, JG: AUTHOR

Abstract

This article describes a closed-boat system that is superior to the other methods for obtaining etch rate uniformity and thus smaller image size tolerances.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 69% of the total text.

Page 1 of 3

Radial Etch Control Boat

This article describes a closed-boat system that is superior to the other methods for obtaining etch rate uniformity and thus smaller image size tolerances.

Figs. 1 through 8 illustrate the control ring designs tried, and Figs. 9 through 11 show the boat design.

Tables I and II show uniformity results for blanket silicon nitride wafers and patterned wafers, respectively.

The conformation numbers shown in Figs. 2 through 8 and Tables I and II refer to the way the rings were arranged. All rings had an outside diameter of 100 mm. The inside diameters were 87 mm, 75 mm and 60 mm for rings 1, 2 and 3, respectively.

Fig. 1 illustrates the patterned or blanket silicon nitride-coated monitor 20. Figs. 2-8 show various combinations of rings 1, 2 and 3 with the monitor. Fig. 8 uses an aluminum shield 22.

Fig. 9 illustrates the front view of the boat having aluminum film 25 shielding the wafers from radial flow and supported by insulator legs 27. The phantom dashed portion shows the top of the boat in its open condition. Fig. 10 shows the side view of the boat with its connecting rods 29 holding the boat securely together. Fig. 11 shows the boat in a perspective view: Etch Depth Pct Uniformity Pct Radial

Conformation +/- 3 Sigma (All Points) Uniformity Angstroms

Fig. 1 3328 +/- 1208 37.4 22.3 2 3243 +/- 932 28.7 19.3

3 3019 +/- 1048 34.7 14.1

4 3066 +/- 853 27.8 20.5

5 3259 +/- 802 24.6 6.7

6 3141 +/- 1088 34.6 12.2

1 3551 +/- 1009 28.4 29.2

7 3349 +/- 593 17.7 2.6

Table II

Trial Conformation Ave. 3 Sigma Tolerance

I 1 .90

7 .75

II 1 1.11

8 .86

The results shown in Tables I and II indicate that any conformation of radial etch control rings improves the within-wafer uniformity but the be...