US-20260125792-A1 - SHOWERHEAD GAS INLET MIXER

Abstract

A showerhead for a substrate processing chamber includes a head portion configured to receive a gas mixture and a stem portion coupled to the head portion. A first plenum is defined within the head portion and the gas mixture flows into the plenum and from the plenum into the substrate processing chamber via holes arranged in a lower surface of the head portion. The stem portion is configured to supply the gas mixture to the head portion through a central bore. A mixing chamber is arranged on the stem portion. The mixing chamber is configured to receive a first gas supplied from a first mixer inlet and a second gas supplied from a second mixer inlet, mix the first gas and the second gas into the gas mixture, and direct the gas mixture into an upper end of the central bore to be supplied downward into the head portion.

Inventors

• Gary B. Lind
• Leonard Kho
• Atul Kumar Garg
• Arun Kumar HOSUR SHIVALINGE GOWDA
• Karl Frederick Leeser

Assignees

• LAM RESEARCH CORPORATION

Dates

Publication Date

20260507

Application Date

20230927

Claims (20)

1. 1 . A showerhead for a substrate processing chamber, the showerhead comprising: a head portion configured to receive at least a first gas mixture, wherein at least a first plenum is defined within the head portion, and wherein the first gas mixture flows into the first plenum and from the first plenum into a deposition zone of the substrate processing chamber via holes arranged in a lower surface of the head portion; a stem portion coupled to the head portion, the stem portion configured to supply the first gas mixture to the head portion through a central bore defined within the stem portion; and a mixing chamber arranged on the stem portion, the mixing chamber configured to (i) receive a first gas supplied from a first mixer inlet and a second gas supplied from a second mixer inlet, (ii) mix the first gas and the second gas into the first gas mixture, and (iii) direct the first gas mixture into an upper end of the central bore to be supplied downward into the head portion.
2. 2 . The showerhead of claim 1 , wherein the mixing chamber is arranged at an upper end of the stem portion around the central bore, and wherein the mixing chamber is configured to direct the first gas mixture upward within the mixing chamber and into the upper end of the central bored.
3. 3 . The showerhead of claim 2 , further comprising a plurality of mixer outlets extending upward from an upper end of the mixing chamber toward the upper end of the central bore.
4. 4 . The showerhead of claim 3 , further comprising a valve assembly arranged above the mixing chamber, wherein the valve assembly is configured to selectively allow fluid communication between the mixer outlets and the upper end of the central bore.
5. 5 . The showerhead of claim 1 , wherein the mixing chamber is configured to receive a third gas supplied from a third mixer inlet and mix the third gas with the first gas and the second gas into the first gas mixture.
6. 6 . The showerhead of claim 5 , wherein the first mixer inlet, the second mixer inlet, and the third mixer inlet are arranged at an angle tangential to an outer surface of the mixing chamber.
7. 7 . The showerhead of claim 5 , wherein the first mixer inlet, the second mixer inlet, and the third mixer inlet are arranged such that the first gas, the second gas, and the third gas are supplied into the mixing chamber at an angle tangential to an inner surface of the mixing chamber.
8. 8 . The showerhead of claim 1 , wherein a bottom surface of the mixing chamber is configured to direct the first gas mixture upward within the mixing chamber.
9. 9 . The showerhead of claim 8 , wherein the bottom surface is curved.
10. 10 . The showerhead of claim 1 , further comprising a first inlet arranged to supply a second gas mixture to the stem portion, the first inlet coupled to a first mixing tube configured to (i) receive at least the first gas and the second gas, (ii) mix the first gas and the second gas into the second gas mixture, and (iii) supply the second gas mixture to a middle zone of the head portion via the first inlet and the stem portion.
11. 11 . The showerhead of claim 10 , further comprising a second inlet arranged to supply a third gas mixture to the stem portion, the second inlet coupled to a second mixing tube configured to (i) receive at least the first gas and the second gas, (ii) mix the first gas and the second gas into the third gas mixture, and (iii) supply the third gas mixture to an edge zone of the head portion via the second inlet and the stem portion.
12. 12 . The showerhead of claim 11 , wherein each of the first mixing tube and the second mixing tube includes at least one of (i) a mixing structure arranged within in an interior volume, (ii) a plurality of projecting features extending radially inward from an interior surface into the interior volume, and (iii) one or more helical grooves defined in the interior surface.
13. 13 . The showerhead of claim 1 , the showerhead comprising: a faceplate having a center zone, a middle zone located radially outside of the center zone, and an edge zone located radially outside of the middle zone, wherein the faceplate includes a first plurality of holes distributed throughout the center zone and the middle zone and a second plurality of holes distributed throughout the edge zone; a middle plate; and a backplate, wherein the middle plate is disposed between the faceplate and the backplate, and wherein the faceplate is configured to receive the first gas mixture supplied to the first plenum and supply the first gas mixture to the deposition zone via the first plurality of holes.
14. 14 . The showerhead of claim 13 , further comprising a first inlet arranged to supply a second gas mixture to the stem portion and a second inlet arranged to supply a third gas mixture to the stem portion.
15. 15 . The showerhead of claim 14 , wherein: the faceplate comprises a middle zone located radially outside of the center zone; the faceplate is configured to receive the second gas mixture in the middle zone via the first inlet of the stem portion and a middle inlet of the head portion; the faceplate comprises an edge zone located radially outside of the middle zone; and the faceplate is configured to receive the third gas mixture in the edge zone via the second inlet of the stem portion and an edge inlet of the head portion.
16. 16 . A showerhead for a substrate processing chamber, the showerhead comprising: a head portion defining a center zone, a middle zone located radially outside of the center zone, and an edge zone located radially outside of the middle zone, the head portion configured to receive a first gas mixture in the center zone, a second gas mixture in the middle zone, and a third gas mixture in the edge zone; a stem portion coupled to the head portion, the stem portion configured to supply the first gas mixture to the center zone of the head portion through a central bore defined within the stem portion, supply the second gas mixture to the middle zone of the head portion through a middle inlet, and supply the third gas mixture to the edge zone of the head portion through an edge inlet; and a mixing chamber arranged on the stem portion, the mixing chamber configured to (i) receive a first gas supplied from a first mixer inlet, a second gas supplied from a second mixer inlet, and a third gas supplied form a third mixer inlet, (ii) mix the first gas, the second gas, and the third gas into the first gas mixture, and (iii) direct the first gas mixture into an upper end of the central bore to be supplied downward into the center zone of the head portion.
17. 17 . The showerhead of claim 16 , further comprising: a first inlet arranged to supply the second gas mixture to the stem portion, the first inlet coupled to a first mixing tube configured to (i) receive the first gas, the second gas, and the third gas and (ii) mix the first gas, the second gas, and the third gas into the second gas mixture; and a second inlet arranged to supply the third gas mixture to the stem portion, the second inlet coupled to a second mixing tube configured to (i) receive the first gas, the second gas, and the third gas and (ii) mix the first gas, the second gas, and the third gas into the third gas mixture.
18. 18 . The showerhead of claim 17 , wherein the first mixer inlet, the second mixer inlet, and the third mixer inlet are arranged such that the first gas, the second gas, and the third gas are supplied into the mixing chamber at an angle approximately tangential to an inner surface of the mixing chamber.
19. 19 . A system, comprising: a substrate processing chamber configured to perform bulk deposition on a substrate; and the showerhead of claim 18 .
20. 20 . The system of claim 19 , further comprising a controller configured to control a gas delivery system to independently supply the first gas, the second gas, and the third gas to each of the mixing chamber, the first mixing tube, and the second mixing tube.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 63/413,841, filed on Oct. 6, 2022. The entire disclosure of the application referenced above is incorporated herein by reference. FIELD The present disclosure relates to a showerhead inlet design for substrate processing systems. BACKGROUND The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. A substrate processing tool typically comprises a plurality of stations in which to perform deposition, etching, and other treatments on substrates such as semiconductor wafers. Examples of processes that may be performed on a substrate comprise a chemical vapor deposition (CVD) process, a chemically enhanced plasma vapor deposition (CEPVD) process, a plasma enhanced chemical vapor deposition (PECVD) process, a sputtering physical vapor deposition (PVD) process, atomic layer deposition (ALD), and plasma enhanced ALD (PEALD). Additional examples of processes that may be performed on a substrate comprise etching (e.g., chemical etching, plasma etching, reactive ion etching, etc.) and cleaning processes. During processing, the substrate is disposed in the processing chamber on a substrate support such as an electrostatic chuck (ESC) or a pedestal. Process gases are introduced and, in some examples, plasma is struck in the processing chamber. The process gases are introduced using a gas distribution device, such as a showerhead. SUMMARY A showerhead for a substrate processing chamber includes a head portion configured to receive at least a first gas mixture and a stem portion coupled to the head portion. At least a first plenum is defined within the head portion and the first gas mixture flows into the first plenum and from the first plenum into a deposition zone of the substrate processing chamber via holes arranged in a lower surface of the head portion. The stem portion is configured to supply the first gas mixture to the head portion through a central bore defined within the stem portion. A mixing chamber is arranged on the stem portion. The mixing chamber is configured to receive a first gas supplied from a first mixer inlet and a second gas supplied from a second mixer inlet, mix the first gas and the second gas into the first gas mixture, and direct the first gas mixture into an upper end of the central bore to be supplied downward into the head portion In other features, the mixing chamber is arranged at an upper end of the stem portion around the central bore and the mixing chamber is configured to direct the first gas mixture upward within the mixing chamber and into the upper end of the central bored. The showerhead further includes a plurality of mixer outlets extending upward from an upper end of the mixing chamber toward the upper end of the central bore. The showerhead further includes a valve assembly arranged above the mixing chamber. The valve assembly is configured to selectively allow fluid communication between the mixer outlets and the upper end of the central bore. In other features, the mixing chamber is configured to receive a third gas supplied from a third mixer inlet and mix the third gas with the first gas and the second gas into the first gas mixture. The first mixer inlet, the second mixer inlet, and the third mixer inlet are arranged at an angle tangential to an outer surface of the mixing chamber. The first mixer inlet, the second mixer inlet, and the third mixer inlet are arranged such that the first gas, the second gas, and the third gas are supplied into the mixing chamber at an angle tangential to an inner surface of the mixing chamber. In other features, a bottom surface of the mixing chamber is configured to direct the first gas mixture upward within the mixing chamber. The bottom surface is curved. The showerhead further includes a first inlet arranged to supply a second gas mixture to the stem portion. The first inlet is coupled to a first mixing tube configured to receive at least the first gas and the second gas, mix the first gas and the second gas into the second gas mixture, and supply the second gas mixture to a middle zone of the head portion via the first inlet and the stem portion. In other features, the showerhead further includes a second inlet arranged to supply a third gas mixture to the stem portion. The second inlet is coupled to a second mixing tube configured to receive at least the first gas and the second gas, mix the first gas and the second gas into the third gas mixture, and supply the third gas mixture to an edge zone of the head portion via the second inlet and the stem portion. Each of the first mixin