Low volume showerhead with porous baffle

• US 10,741,365 B2
• Filed: 03/25/2015
• Issued: 08/11/2020
• Est. Priority Date: 05/05/2014
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Chandrasekharan, Ramesh, Sangplung, Saangrut, Swaminathan, Shankar, Pasquale, Frank L., Kang, Hu, LaVoie, Adrien
• Primary Examiner(s): Lund, Jeffrie R
• Assistant Examiner(s): Antolin, Stanislav
• Application Number:
  US14/668,511
• Publication Number:
  US 20150315706A1
• Time in Patent Office: 1,966 Days
• CPC Class Codes: C23C 16/45544 characterized by the apparatus
• CPC Class Codes: C23C 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/45591 Fixed means, e.g. wings, baffles
• CPC Class Codes: C30B 25/14 Feed and outlet means for the gases; Modifying the flow of the reactive gases
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow

Abstract

A low volume showerhead in a semiconductor processing apparatus can include a porous baffle to improve the flow uniformity and purge time during atomic layer deposition. The showerhead can include a plenum volume, one or more gas inlets in fluid communication with the plenum volume, a faceplate including a plurality of first through-holes for distributing gas onto a substrate in the semiconductor processing apparatus, and a porous baffle positioned in a region between the plenum volume and the one or more gas inlets. The one or more gas inlets can include a stem having a small volume to improve purge time. The baffle can be porous and positioned between the stem and the plenum volume to improve flow uniformity and avoid jetting.

Claims

1. A showerhead for use in a semiconductor processing apparatus, the showerhead comprising:

a plenum volume having a first surface and a second surface opposite the first surface, the first surface and the second surface at least partially defining the plenum volume of the showerhead;

a faceplate including a plurality of first through-holes, the plurality of first through-holes extending from a first side to a second side of the faceplate, the first side of the faceplate defining the first surface of the plenum volume;

a backplate opposite the faceplate;

wherein a side of the backplate defines a second surface of the plenum volume;

a stem connected to the backplate and in fluid communication with the plenum volume; and

a baffle plate including a plurality of second through-holes, the baffle plate being positioned at least partially within or fully within a region between the plenum volume and the stem, wherein the region is recessed into the side of the backplate and is in direct fluid communication with the plenum volume and direct fluid communication with the stem.

2. The showerhead of claim 1, wherein a diameter of the faceplate is at least four times greater than a diameter of the baffle plate.

3. The showerhead of claim 2, wherein the diameter of the faceplate is at least ten times greater than the diameter of the baffle plate.

4. The showerhead of claim 1, further comprising:

one or more gas inlets in the stem configured to deliver gas to the plenum volume, wherein the baffle plate is mounted in the recessed region below the one or more gas inlets and above the plenum volume.

5. The showerhead of claim 1, wherein a volume of the stem is between about 1 milliliter and about 50 milliliters.

6. The showerhead of claim 1, wherein each of the stem, the recessed region, and the plenum volume defines a cylindrical volume, and wherein a diameter of the plenum volume is greater than a diameter of the recessed region, and the diameter of the recessed region is greater than a diameter of the stem.

7. The showerhead of claim 1, wherein a volume of the showerhead is between about 50 milliliters and about 500 milliliters.

8. The showerhead of claim 7, wherein the volume of the showerhead is between about 100 milliliters and about 300 milliliters.

9. The showerhead of claim 1, wherein a porosity of the baffle plate is between about 5% and about 25%.

10. The showerhead of claim 1, wherein the plurality of second through-holes are positioned more towards the edges of the baffle plate than the center of the baffle plate.

11. The showerhead of claim 1, wherein the baffle plate is substantially centered on the stem and substantially parallel to the first surface and the second surface.

12. The showerhead of claim 1, wherein a number of first through-holes is between about 1500 and about 2500 through-holes.

13. The showerhead of claim 1, wherein the plurality of first through-holes are arranged in a triangular arrangement on the faceplate and the second through-holes are arranged in a hexagonal arrangement on the baffle plate.

14. A semiconductor processing station, the semiconductor processing station including the showerhead of claim 1.

15. The semiconductor processing station of claim 14, further comprising:

a controller configured with instructions to perform the following operations;

providing a substrate into the semiconductor processing station;

introducing reactant gas into the semiconductor processing station through the showerhead to adsorb onto the surface of the substrate;

introducing a purge gas into the semiconductor processing station through the showerhead; and

applying a plasma to form a thin film layer from the adsorbed reactant gas on the surface of the substrate.

16. The semiconductor processing station of claim 15, wherein a film non-uniformity of the thin film layer is less than about 0.5%.

17. The semiconductor processing station of claim 16, wherein the film non-uniformity is decoupled from one or more process parameters associated with one or more of introducing the gas reactant, introducing the purge gas, and applying the plasma.

18. The semiconductor processing station of claim 15, wherein forming the thin film layer in an atomic layer deposition (ALD) cycle is performed in less than about 1.5 seconds.

19. A semiconductor processing tool, the semiconductor processing tool including the semiconductor processing station of claim 15.

20. The semiconductor processing tool of claim 19, wherein the semiconductor processing tool includes a stepper.