Direct outlet toroidal plasma source

• US 10,573,496 B2
• Filed: 12/09/2014
• Issued: 02/25/2020
• Est. Priority Date: 12/09/2014
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Lubomirsky, Dmitry
• Primary Examiner(s): Dhingra, Rakesh K
• Assistant Examiner(s): Chan, Laureen
• Application Number:
  US14/565,046
• Publication Number:
  US 20160163512A1
• Time in Patent Office: 1,904 Days
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32357 Generation remote from the workpiece, e.g. down-stream
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow
• CPC Class Codes: H01J 37/32458 Vessel
• CPC Class Codes: H01J 37/3266 Magnetic control means
• CPC Class Codes: H01J 37/32807 Construction (includes replacing parts of the apparatus)
• CPC Class Codes: H05H 1/46 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/26 takes precedence
• CPC Class Codes: H05H 1/4652 using inductive coupling means, e.g. coils
• CPC Class Codes: Y02E 30/10 Nuclear fusion reactors

Abstract

An apparatus for supplying plasma products includes a plasma generation block that defines a toroidal plasma cavity therein. The plasma cavity is substantially symmetric about a toroidal axis, and the toroidal axis defines a first and second axial side of the plasma generation block. A magnetic element at least partially surrounds the plasma generation block at one azimuthal location with respect to the toroidal axis, such that a magnetic flux within the magnetic element induces a corresponding electric field into the plasma cavity to generate a plasma from one or more source gases, the plasma forming plasma products. The plasma generation block supplies the plasma products through a plurality of output apertures defined by the plasma generation block on the first axial side.

Claims

1. An apparatus for supplying plasma products, comprising:

first and second plasma generation blocks;

first and second magnetic elements partially encircling the first and second plasma generation blocks respectively;

a first plate defining a plurality of first openings therethrough;

a diffuser plate defining a plurality of second openings;

and a domain separator disposed within a space between the first plate and the diffuser plate, the domain separator forming an annular feature in contact with an underside of the first plate and an upper side of the diffuser plate;

wherein;

the first and second plasma generation blocks define respective first and second toroidal plasma cavities, each of the first and second toroidal plasma cavities being substantially symmetric about a toroidal axis that defines a first and second axial side of the first and second plasma generation blocks, and configured such that when in operation, magnetic fluxes within the first and second magnetic elements induce electric fields into the first and second toroidal plasma cavities to generate first and second plasma products, respectively;

each of the first and second plasma generation blocks includes a respective member that bounds the respective toroidal plasma cavity on a radially inward side, a radially outward side, and the second axial side thereof, each respective member forming radially inward and outward edges;

the first plate is disposed on a first axial side of the first and second plasma generation blocks;

an upper surface of the first plate contacts the radially inward and radially outward edges of each respective member such that the respective first and second toroidal plasma cavities are in fluid communication with ones of the plurality of first openings;

the first and second plasma generation blocks are configured to supply the respective first and second plasma products through the one or more first openings;

the domain separator separates the first and second plasma products in the space between the first plate and the diffuser plate;

the first and second plasma products flow independently through ones of the plurality of second openings, toward a process chamber; and

wherein the domain separator has an outer diameter that is less than the diameter of the first toroidal plasma cavity and greater than the diameter of the second toroidal plasma cavity.

2. The apparatus for supplying plasma products of claim 1, wherein the first plasma generation block defines one or more inlet apertures for supplying the one or more first source gases to the first toroidal plasma cavity.

3. The apparatus for supplying plasma products of claim 2, further comprising an inlet gas manifold disposed adjacent to the second axial side of the first plasma generation block, the one or more inlet apertures comprising a plurality of apertures defined by the first plasma generation block on the second axial side, for supplying the one or more first source gases from the inlet gas manifold to the first toroidal plasma cavity.

4. The apparatus for supplying plasma products of claim 1, wherein the first plasma generation block comprises aluminum.

5. The apparatus for supplying plasma products of claim 4, wherein the first plasma generation block comprises at least one dielectric break that is configured to interrupt azimuthal current induced by the electric field.

6. The apparatus for supplying plasma products of claim 5, wherein the dielectric break comprises a plurality of dielectric breaks that are substantially symmetrically distributed azimuthally about the first plasma generation block.

7. The apparatus for supplying plasma products of claim 5, wherein the one or more first openings extend through the at least one dielectric break.

8. The apparatus for supplying plasma products of claim 1, wherein the radially inward edge of the first member and the radially outward edge of the first member abut the first plate adjacent to ones of the first openings.

9. An apparatus for supplying plasma products, comprising:

a first plasma generation block that defines a first toroidal plasma cavity therein, a shape of the first toroidal plasma cavity being substantially symmetric about a toroidal axis, the toroidal axis defining a first and second axial side of the first plasma generation block, wherein the first plasma generation block includes;

a first member that bounds the first toroidal plasma cavity on a radially inward side, a radially outward side, and the second axial side thereof, the first member forming radially inward and outward edges that are coplanar with one another; and

a plate on the first axial side of the first toroidal plasma cavity that;

forms an upper surface that extends, along a single plane, from radially inward of the radially inward edge of the first member, to radially outward of the radially outward edge of the first member,

defines one or more first openings therethrough that are substantially azimuthally continuous about the toroidal axis, and

contacts the radially inward and radially outward edges of the first member at the single plane; and

at least two magnetic elements adjacent to the first toroidal plasma cavity, that partially encircle the first toroidal plasma cavity, and configured such that when in operation, magnetic fluxes within the magnetic elements induce a corresponding electric field into the first toroidal plasma cavity to generate a first plasma from one or more first source gases, and the first plasma forms a first portion of the plasma products;

wherein the first plasma generation block is configured to supply the first portion of the plasma products through the one or more first openings defined by the plate;

the apparatus further comprising;

a second plasma generation block that defines a second toroidal plasma cavity therein, a shape of the second toroidal plasma cavity being substantially symmetric about the toroidal axis, the toroidal axis defining a first and second axial side of the second plasma generation block, wherein the second plasma generation block;

is characterized by a smaller diameter than a diameter of the first plasma generation block, and

includes a second member that bounds the second toroidal plasma cavity on a radially inward side, a radially outward side, and the second axial side thereof, the second member forming radially inward and outward edges that are coplanar with one another; and

at least two magnetic elements adjacent to the second toroidal plasma cavity, that partially encircle the second toroidal plasma cavity such that when in operation, magnetic fluxes within the magnetic elements induce a corresponding electric field into the second toroidal plasma cavity to generate a second plasma from one or more second source gases, and the second plasma forms a second portion of the plasma products; and

wherein;

the plate defines one or more second openings therethrough that are substantially azimuthally continuous about the toroidal axis, and

the second plasma generation block is configured to supply the second portion of the plasma products through the one or more second openings defined by the plate;

the apparatus further comprising;

a diffuser plate that;

has a diameter greater than a diameter of the first toroidal plasma cavity,

adjoins an underside of the plate at peripheral edges of the diffuser plate, such that a space forms between the plate and a proximal side of the diffuser plate, and

forms a plurality of apertures therethrough,

such that when in operation, the first and second portions of the plasma products pass from the first and second toroidal plasma cavities, through the first and second openings, into the space, and through the apertures of the diffuser plate toward a process chamber;

the apparatus further comprising a domain separator characterized as an annular feature having an outer diameter that is less than the diameter of the first toroidal plasma cavity and greater than the diameter of the second toroidal plasma cavity, wherein the domain separator contacts both the plate and the diffuser plate, and is configured to separate the first and second portions of the plasma products within the space.

10. The apparatus for supplying plasma products of claim 9, wherein an outermost extent of the domain separator is radially inward of the one or more first openings in the plate, and an innermost extent of the domain separator is radially outward of the one or more second openings in the plate.

11. The apparatus for supplying plasma products of claim 9, further comprising provisions for independently controlling the first source gases and the second source gases, to provide control over process differences between a center region of the process chamber and an edge region of the process chamber.

12. The apparatus for supplying plasma products of claim 9, wherein the one or more first openings through the plate extend radially from the radially inward edge of the first member to the radially outward edge of the first member, and the one or more second openings through the plate extend radially from the radially inward edge of the second member to the radially outward edge of the second member.