VARIABLE SHOWERHEAD FLOW BY VARYING INTERNAL BAFFLE CONDUCTANCE

• US 20160020074A1
• Filed: 07/17/2015
• Published: 01/21/2016
• Est. Priority Date: 08/31/2012
• Status: Active Grant

• Current Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Original Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Inventors: Mohn, Jonathan D., Hamilton, Shawn M., te Nijenhuis, Harald, Lorelli, Jeffrey E., Madrigal, Kevin
• Granted Patent: US 9,728,380 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C23C 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/45589 Movable means, e.g. fans
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32633 Baffles

Abstract

Apparatuses and techniques for providing for variable radial flow conductance within a semiconductor processing showerhead are provided. In some cases, the radial flow conductance may be varied dynamically during use. In some cases, the radial flow conductance may be fixed but may vary as a function of radial distance from the showerhead centerline. Both single plenum and dual plenum showerheads are discussed.

Claims

1. (canceled)

2. An apparatus comprising:

an outer wall, the outer wall substantially axially symmetric about a first axis;

a first inlet;

a second inlet; and

a dual plenum volume substantially defined by the outer wall, the dual plenum volume divided into an even number of sub-volumes by radial barriers substantially extending from locations proximate to the first axis to the outer wall, wherein;

each sub-volume has a plurality of plenum gas distribution holes passing through a bottom portion of the outer wall,

the odd sub-volumes form a first plenum volume,

the even sub-volumes form a second plenum volume,

the first inlet is configured to supply a first process gas to the odd sub-volumes,

the second inlet is configured to supply a second process gas to the even sub-volumes,

the first plenum volume is fluidically isolated from the second plenum volume between the plenum gas distribution holes and the first inlet, and

the second plenum volume is fluidically isolated from the first plenum volume between the plenum gas distribution holes and the second inlet.

3. The apparatus of claim 2, wherein the sub-volumes are all substantially the same size and overall shape.

4. The apparatus of claim 2, wherein one or more of the sub-volumes is further partitioned into two or more sub-sub-volumes by one or more additional radial barriers and wherein each of the sub-sub-volumes of a sub-volume is configured to be supplied the same process gas.

5. The apparatus of claim 2, further comprising:

a first gas feed tube with a first interior volume, and

a second gas feed tube, wherein;

the first gas feed tube is concentric with the second gas feed tube, thereby creating an annular, second interior volume between the first gas feed tube and the second gas feed tube,

the first interior volume is configured to convey the first process gas from the first inlet to the odd sub-volumes, and

the second interior volume is configured to convey the second process gas from the second inlet to the even sub-volumes.

6. The apparatus of claim 5, wherein the first gas feed tube includes a stepped-up region where the diameter of the first gas feed tube is larger than the diameter of the first gas feed tube.

7. The apparatus of claim 6, wherein the stepped-up region includes channels that extend in a direction parallel to the first axis, wherein:

each channel is in fluidic communication with the second interior volume, and

each channel serves as a fluidic connection between the second interior volume and one of the even sub-volumes.

8. The apparatus of claim 7, wherein the stepped-up region includes slots that extend radially from the first interior volume and through the first gas feed tube, wherein:

each slot is in fluidic communication with the first interior volume, and

each slot serves as a fluidic connection between the first interior volume and one of the odd sub-volumes.

9. The apparatus of claim 8, wherein each slot is interposed between neighboring channels and each channel is interposed between neighboring slots.

10. The apparatus of claim 2, wherein the sub-volumes decrease in height along the first axis as a function of radial position with respect to the first axis.

11. The apparatus of claim 2, wherein the sub-volumes increase in height along the first axis as a function of radial position with respect to the first axis.

12. The apparatus of claim 2, wherein there are at least 10 sub-volumes.

13. The apparatus of claim 2, wherein the number of sub-volumes is an even number of sub-volumes greater than or equal to 10 sub-volumes and less than or equal to 24 sub-volumes.

14. The apparatus of claim 2, further comprising a faceplate, wherein the faceplate includes a plurality of gas distribution holes through the faceplate and is positioned such that openings of the gas distribution holes face the plenum gas distribution holes in the outer wall.

19. The apparatus of claim 2, wherein the sub-volumes decrease in height along the first axis as a function of radial position with respect to the first axis.

20. The apparatus of claim 2, wherein the sub-volumes increase in height along the first axis as a function of radial position with respect to the first axis.

21. The apparatus of claim 2, wherein the number of sub-volumes is an even number of sub-volumes greater than or equal to 10 sub-volumes and less than or equal to 24 sub-volumes.

15. A semiconductor processing tool comprising:

a semiconductor processing chamber; and

a dual-plenum showerhead, the dual-plenum showerhead including;

an outer wall, the outer wall substantially axially symmetric about a first axis;

a first inlet;

a second inlet; and

a dual plenum volume substantially defined by the outer wall, the dual plenum volume divided into an even number of sub-volumes by radial barriers substantially extending from locations proximate to the first axis to the outer wall, wherein;

each sub-volume has a plurality of plenum gas distribution holes passing through a bottom portion of the outer wall,

the odd sub-volumes form a first plenum volume,

the even sub-volumes form a second plenum volume,

the first inlet is configured to supply a first process gas to the odd sub-volumes,

the second inlet is configured to supply a second process gas to the even sub-volumes,

the first plenum volume is fluidically isolated from the second plenum volume between the plenum gas distribution holes and the first inlet,

the second plenum volume is fluidically isolated from the first plenum volume between the plenum gas distribution holes and the second inlet, and

the dual-plenum showerhead is configured to deliver the first process gas and the second process gas to a semiconductor wafer when the semiconductor wafer within the semiconductor processing chamber.

16. The semiconductor processing tool of claim 15, wherein the faceplate is offset from the outer wall in a direction parallel to the first axis by a gap.

an outer wall, the outer wall substantially axially symmetric about a first axis;

a first inlet;

a second inlet; and

a dual plenum volume substantially defined by the outer wall, the dual plenum volume divided into an even number of sub-volumes by radial barriers substantially extending from locations proximate to the first axis to the outer wall, wherein;

each sub-volume has a plurality of plenum gas distribution holes passing through a bottom portion of the outer wall,

the odd sub-volumes form a first plenum volume,

the even sub-volumes form a second plenum volume,

the first inlet is configured to supply a first process gas to the odd sub-volumes,

the second inlet is configured to supply a second process gas to the even sub-volumes,

the first plenum volume is fluidically isolated from the second plenum volume between the plenum gas distribution holes and the first inlet, and

the second plenum volume is fluidically isolated from the first plenum volume between the plenum gas distribution holes and the second inlet.

17. The apparatus of claim 15, wherein the sub-volumes are all substantially the same size and overall shape.

18. The apparatus of claim 15, wherein one or more of the sub-volumes is further partitioned into two or more sub-sub-volumes by one or more additional radial barriers and wherein each of the sub-sub-volumes of a sub-volume is configured to be supplied the same process gas.