CVD apparatus with gas delivery ring

Patent metadata

Field	Value
Publication number	US-9741575-B2
Application number	US-201414202308-A
Country	US
Kind code	B2
Filing date	Mar 10, 2014
Priority date	Mar 10, 2014
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

The present disclosure relates to a chemical vapor deposition apparatus and associated methods. In some embodiments, the CVD apparatus has a vacuum chamber and a gas import having a gas import axis through which a process gas is imported into the vacuum chamber and being arranged near an upper region of the vacuum chamber. At least one exhaust port is arranged near a bottom region of the vacuum chamber. The CVD apparatus also has a gas delivery ring with an outlet disposed under the gas import. A pressure near the outlet of the gas delivery ring is smaller than that of the rest of the vacuum chamber.

First claim

What is claimed is:

1. A chemical vapor deposition (CVD) apparatus comprising:
a vacuum chamber;
a wafer chuck having a chuck surface configured to receive a semiconductor substrate;
a gas import having a gas import axis through which a process gas is imported into the vacuum chamber and being arranged near an upper region of the vacuum chamber;
at least one exhaust port arranged near a bottom region of the vacuum chamber;
a showerhead arranged in the upper region of the vacuum chamber and configured to redistribute the process gas from the gas import;
a gas delivery ring attached to a sidewall of the vacuum chamber over the wafer chuck and between the gas import and the exhaust port; and
an inert gas supply located external to the vacuum chamber and coupled to the gas delivery ring and configured to deliver an inert gas to an inlet of the gas delivery ring;
wherein the gas delivery ring is configured to expel the inert gas from an outlet of the gas delivery ring, and wherein the outlet has a smaller cross-sectional area than the inlet, causing the outlet to deliver the inert gas at a first pressure within a cylindrically shaped region above an outer circumferential edge of the semiconductor substrate that is less than a second pressure of a rest of the vacuum chamber, the first pressure is configured to pull a flow of the process gas from the showerhead to redirect the process gas from the showerhead to an area near the outlet;
wherein the gas delivery ring has a curved outer wall that overlaps a curved inner wall and that protrudes laterally past the curved inner wall to extend to an innermost point of the gas delivery ring, wherein a space between the overlap of the curved outer wall and the curved inner wall defines the outlet in a downward facing direction, wherein the outlet is located between an uppermost point and a lowermost point of the gas delivery ring, wherein the innermost point of the gas delivery ring and the outlet of the gas delivery ring are disposed above a lowermost surface of the showerhead.

2. The CVD apparatus of claim 1 , wherein the inlet is located at a lower region of the curved outer wall of the gas delivery ring.

3. The CVD apparatus of claim 1 , wherein the gas delivery ring comprises a hollow duct in communication with the outlet and having a lower surface that extends below the lowermost surface of the showerhead.

4. The CVD apparatus of claim 1 , wherein the gas delivery ring comprises a hollow duct having an upper region protruding above the inlet and a lower region protruding below of the inlet, wherein the upper region has a greater width than the lower region.

5. The CVD apparatus of claim 1 , wherein the outlet of the gas delivery ring comprises a series of separate openings symmetrically spaced at the curved inner wall of the gas delivery ring.

6. The CVD apparatus of claim 1 , wherein the gas delivery ring is coupled to a sidewall of the vacuum chamber having a substantially same lateral dimension with that of the vacuum chamber, wherein the gas delivery ring has a spindle shape that is widest at a middle upper region and tapering more sharply at a bottom end than a top end.

7. The CVD apparatus of claim 1 , wherein the outlet of the gas delivery ring is located at a widest position of the gas delivery ring, wherein the curved outer wall has an apex located at a topmost point of the gas delivery ring.

8. The CVD apparatus of claim 1 , wherein the upper region of the vacuum chamber is a dome or a flange.

9. The CVD apparatus of claim 1 , wherein the wafer chuck is moveable and arranged at a lower section of the vacuum chamber.

10. The CVD apparatus of claim 9 , wherein the gas delivery ring is configured to redirect the process gas, which flows through the vacuum chamber reaching a surface of the wafer chuck, so the redirected process gas uniformly reaches the surface of the wafer chuck at central and edge regions.

11. The CVD apparatus of claim 9 , wherein a lateral dimension of the showerhead is approximately equal to that of the wafer chuck.

12. The CVD apparatus of claim 11 , wherein the gas delivery ring is attached to an outer sidewall of the showerhead having a substantially same lateral dimension with that of the vacuum chamber.

13. The CVD apparatus of claim 11 , wherein the showerhead further comprises a plurality of apertures formed there through with at least two different diameters.

14. The CVD apparatus of claim 1 , further comprising: a heating system or cooling system to heat or cool the semiconductor substrate.

15. The CVD apparatus of claim 1 , wherein the CVD apparatus is a plasma-enhanced chemical vapor deposition (PECVD), atmospheric pressure CVD, or metalorganic CVD apparatus.

16. An apparatus for distributing a process gas within a chamber, comprising:
a gas import disposed at one side of the chamber and an exhaust port disposed at an opposite side of the chamber, wherein the process gas flows through the chamber from the gas import to the exhaust port;
a wafer chuck arranged between the gas import and the exhaust port and having a chuck surface to hold a semiconductor substrate;
a showerhead arranged in an upper region of the chamber and configured to redistribute the process gas from the gas import, wherein a lateral dimension of the showerhead is approximately equal to that of the wafer chuck;
a gas delivery ring having a curved outer wall that overlaps a curved inner wall and that protrudes laterally past the curved inner wall to extend to an innermost point of the gas delivery ring, wherein a space between the overlap of the curved outer wall and the curved inner wall defines an outlet in a downward facing direction, wherein the innermost point of the gas delivery ring and the outlet of the gas delivery ring are disposed above a lowermost surface of the showerhead; and
a carrier gas supply external to the chamber and coupled to the gas delivery ring, the carrier gas supply configured to deliver a carrier gas, which is different from the process gas, from external to the chamber to an inlet of the gas delivery ring, wherein the carrier gas flows from the inlet of the gas delivery ring to the outlet of the gas delivery ring;
wherein the outlet has a smaller cross-sectional area than the inlet, causing the outlet to deliver the carrier gas at a first pressure within a cylindrically shaped region above an outer circumferential edge of the semiconductor substrate that is less than a second pressure of a rest of the chamber, the first pressure is configured to pull a flow of the process gas from the showerhead to redirect the process gas from the showerhead to an area near the outlet;
wherein an upper portion of the gas delivery ring, which has a first ring width and includes the outlet, is laterally adjacent to an outermost sidewall of the showerhead, and a lower portion of the gas delivery ring, which has a second ring width that is less than the first ring width, includes the inlet and an angled sidewall which extends downwardly to a height that is below the outlet of the gas delivery ring and the lowermost surface of the showerhead.

17. The apparatus of claim 16 , wherein the process gas is redistributed by a pressure difference of an area near the outlet of the gas delivery ring and the rest of the chamber, such that a distribution of the process gas is uniform when flows by the wafer chuck.

18. The apparatus of claim 16 , wherein the showerhead has a plurality of apertures formed there-through to redistribute the process gas, wherein the gas delivery ring is attached to the outermost s

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Lin Hsiang-Wei
• Chen Chia-Ho

Classifications

• H10P14/40 Primary

  of conductive or resistive materials · CPC title

• C23C16/45565 Primary

  Shower nozzles · CPC title

• C23C16/45574

  Nozzles for more than one gas · CPC title

• H01L21/28506 Primary

  Electricity · mapped topic

• C23C16/45519

  Inert gas curtains · CPC title