Ring-shaped high-density plasma source and method
First Claim
1. A source for producing a high-density, inductively coupled plasma with RF energy in a vacuum processing chamber comprising:
- a dielectric material having a surface in contact with a processing gas within a vacuum processing chamber;
an RF coil isolated from the processing gas by the dielectric material and having a plurality of segments including at least first segments thereof collectively forming a generally circularly-shaped ring proximate the dielectric material; and
a permanent magnet assembly configured and positioned to generate a ring-shaped magnetic tunnel in the processing chamber adjacent said surface of the dielectric material and opposite from and generally aligned with the circularly-shaped ring formed by said first segments of the coil such that RF energy couples from the first segments of the coil into a volume of the gas enclosed by the ring-shaped magnetic tunnel inside of the chamber.
1 Assignment
0 Petitions
Accused Products
Abstract
A processing system for processing a substrate with a plasma is provided with an antenna for producing a ring-shaped inductively coupled plasma in a vacuum processing chamber particularly useful for coating or etching semiconductor wafer substrates. A three-dimensional antenna in the form of a coil provides spacial distribution of plasma parameters in a ring-shaped region inside of the chamber that can be adapted to specific physical and process requirements. An axially symmetric permanent magnet assembly enhances the ring-shaped concentration of a high-density inductively coupled plasma by trapping the plasma in the ring-shaped region near the inside of a dielectric window located in the chamber wall in close proximity to segments of the antenna that lie adjacent the outside of the window.
-
Citations
39 Claims
-
1. A source for producing a high-density, inductively coupled plasma with RF energy in a vacuum processing chamber comprising:
-
a dielectric material having a surface in contact with a processing gas within a vacuum processing chamber;
an RF coil isolated from the processing gas by the dielectric material and having a plurality of segments including at least first segments thereof collectively forming a generally circularly-shaped ring proximate the dielectric material; and
a permanent magnet assembly configured and positioned to generate a ring-shaped magnetic tunnel in the processing chamber adjacent said surface of the dielectric material and opposite from and generally aligned with the circularly-shaped ring formed by said first segments of the coil such that RF energy couples from the first segments of the coil into a volume of the gas enclosed by the ring-shaped magnetic tunnel inside of the chamber. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
the RF coil is a three-dimensional coil having at least one second segment thereof extending relatively remote from said surface of the dielectric material than the first segments such that some lines of magnetic flux pass between a first and a second segment without passing through the dielectric material.
-
-
3. The plasma producing source of claim 1 wherein:
the RF coil is a three-dimensional coil having at least one curved second segment thereof lying in a plane that intersects the dielectric material, the first segments thereof being curved and lying in a plane generally parallel to the dielectric material.
-
4. The plasma producing source of claim 1 wherein:
the RF coil is a three-dimensional coil having at least one curved second segment of approximately one-half turn lying in a plane that intersects the dielectric material, a plurality of the first segments each being curved and of approximately one-half turn each lying in a plane generally parallel to the dielectric material.
-
5. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil including;
at least one curved second segment of approximately one-half turn lying in a plane that intersects the dielectric material, and at least one pair of the first segments are curved and are oriented such that current in the segments of the pair flows around the ring in opposite directions, each approximately one-half turn and lying in a plane generally parallel to the dielectric material.
-
-
6. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil including;
a plurality of curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, and at least two pairs of the first segments, the first segments of each pair;
being curved and are oriented such that current in the segments of the pair flows therein around the ring in opposite directions, each approximately one-half turn and lying in a plane generally parallel to the dielectric material.
-
-
7. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
a plurality of curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, and at least two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, one clockwise and one counterclockwise, each approximately one-half turn and lying in a plane generally parallel to the dielectric material; and
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then at least one other segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
8. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
a plurality of at least three curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, and at least two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, one clockwise and one counterclockwise, each approximately one-half turn and lying in a plane generally parallel to the dielectric material; and
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then at least one second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
9. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
three curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, and two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, one clockwise and one counterclockwise, each approximately one-half turn and lying in a plane generally parallel to the dielectric material; and
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then a second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
10. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil including;
a plurality of curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, at least two pairs of the first segments, the first segments of each pair;
being curved and are oriented such that current in the segments of the pair flows therein around the ring in opposite directions, each approximately one-half turn and lying in a plane generally parallel to the dielectric material; and
at least one relatively straight intermediate segment lying in the plane containing the pairs of first segments.
-
-
11. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
a plurality of curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, at least two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, each approximately one-half turn and lying in a plane generally parallel to the dielectric material;
at least one relatively straight intermediate segment lying in the plane containing the pairs of first segments; and
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then an intermediate segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
12. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
two curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, each approximately one-half turn and lying in a plane generally parallel to the dielectric material;
one relatively straight intermediate segment lying in the plane containing the pairs of first segments and oriented such that magnetic field lines encircling the intermediate segment in a plane perpendicular thereto circulate in a direction opposite magnetic field lines encircling the first segments in the same plane; and
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then the intermediate segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
13. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
a plurality of at least four curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, at least two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, each approximately one-half turn and lying in a plane generally parallel to the dielectric material;
at least one relatively straight intermediate segment lying in the plane containing the pairs of first segments and oriented such that magnetic field lines encircling the intermediate segment in a plane perpendicular thereto circulate in a same direction as magnetic field lines encircling the first segments in the same plane; and
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then a second segment, then an intermediate segment, then a second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
14. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
four curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, each approximately one-half turn and lying in a plane generally parallel to the dielectric material;
one relatively straight intermediate segment lying in the plane containing the pairs of first segments and oriented such that magnetic field lines encircling the intermediate segment in a plane perpendicular thereto circulate in a same direction as magnetic field lines encircling the first segments in the same plane; and
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then a second segment, then the intermediate segment, then a second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
15. The plasma producing source of claim 1 further comprising:
a Faraday shield inside the chamber, closely spaced from the dielectric material and generally parallel thereto.
-
16. The plasma producing source of claim 1 further comprising:
a Faraday shield inside the chamber, closely spaced from the dielectric material and generally parallel thereto, the shield having a plurality of slots therethrough that, immediately opposite the dielectric material from the first segments, lie in planes generally perpendicular to the first segments.
-
17. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
a three curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, and two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, one clockwise and one counterclockwise, each approximately one-half turn and lying in a plane generally parallel to the dielectric material;
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then a second segment, then a counterclockwise extending first segment;
thena second segment, then a counterclockwise extending first segment; and
a Faraday shield inside the chamber, closely spaced from the dielectric material and generally parallel thereto, the shield having a plurality of slots therethrough that, immediately opposite the dielectric material from the ring, are oriented in a generally radial direction.
-
-
18. The plasma producing source of claim 1 wherein:
-
the RF coil is a three-dimensional coil and the plurality of segments includes;
a plurality of curved second segments, each approximately one-half turn and lying in a plane that intersects the dielectric material, at least two pairs of the first segments, the first segments of each pair;
being curved and oriented such that current in the segments of the pair flows therein around the ring in opposite directions, each approximately one-half turn and lying in a plane generally parallel to the dielectric material;
at least one relatively straight intermediate segment lying in the plane containing the pairs of first segments;
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then an intermediate segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment; and
a Faraday shield inside the chamber, closely spaced from the dielectric material and generally parallel thereto, the shield having a plurality of slots therethrough that, immediately opposite the dielectric material from the ring, are oriented in a generally radial direction and immediately opposite the dielectric material from the each intermediate segment lie in planes generally perpendicular to the intermediate segment.
-
-
19. The plasma producing source of claim 18 wherein:
-
the plurality of curved second segments includes at least four second segments; and
the segments are formed of the single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then a second segment, then an intermediate segment, then a second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment; and
a Faraday shield inside the chamber, closely spaced from the dielectric material and generally parallel thereto, the shield having a plurality of slots therethrough that, immediately opposite the dielectric material from the ring, are oriented in a generally radial direction and immediately opposite the dielectric material from the each intermediate segment lie in planes generally perpendicular to the intermediate segment.
-
-
20. The plasma producing source of claim 1 wherein the permanent magnet assembly includes:
-
an inner magnet having a generally circular outer perimeter forming a first pole spaced radially inward of the ring, and an annular outer magnet having an inner perimeter forming a second pole having a polarity that is magnetically opposite the polarity of the first pole, spaced radially outward of the ring.
-
-
21. The plasma producing source of claim 1 wherein the permanent magnet assembly is located adjacent the dielectric material outside of the chamber.
-
22. The plasma producing source of claim 1 further comprising:
a Faraday shield inside the chamber, closely spaced from the dielectric material and generally parallel thereto, the permanent magnet assembly being located adjacent the shield inside of the chamber.
-
23. An etching apparatus comprising the plasma producing source of claim 1 and further comprising:
-
the vacuum chamber;
an RF power source connected to the RF coil; and
a substrate support within the chamber.
-
-
24. An ionized physical deposition apparatus comprising the plasma producing source of claim 1 and further comprising:
-
the vacuum chamber;
an RF power source connected to the RF coil;
a substrate support within the chamber; and
a magnetron sputtering cathode for sputtering material into a region within the chamber containing the high-density inductively coupled plasma.
-
-
25. An RF antenna for inductively coupling energy into a vacuum processing chamber for sustaining a high-density plasma therein comprising:
-
a three-dimensional coil having a plurality of segments including;
at least two pairs of half-turn semi-circular first segments arranged in a ring and lying in a first plane, the first segments being interconnected to conduct current in opposite directions, one clockwise and one counterclockwise, around the ring, and a plurality of curved second segments, each approximately one-half turn and each extending substantially outside of the first plane and lying in a plane that intersects the first plane;
the segments being formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then at least one other segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment. - View Dependent Claims (26, 27, 28, 29, 30, 31, 32, 33, 34)
the at least one segment arranged between the clockwise extending first segment and the counterclockwise extending first segment includes at least one second segment.
-
-
27. The antenna of claim 25 wherein:
the second segments extend from the first plane a distance approximately half the diameter of the ring.
-
28. The antenna of claim 25 wherein:
-
the plurality of curved second segments includes at least three curved second segments; and
the segments formed of the single series conductor are arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then at least one second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
29. The antenna of claim 25 wherein:
-
the plurality of curved second segments consists of three curved second segments;
the at least two pairs of first segments consists of two pairs of the first segments; and
the segments formed of the single series conductor are arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then a second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
30. The antenna of claim 25 wherein:
the plurality of segments further includes at least one relatively straight intermediate segment lying in the first plane.
-
31. The antenna of claim 25 wherein:
-
the plurality of segments further includes at least one relatively straight intermediate segment lying in the first plane; and
the segments formed of the single series conductor are arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then an intermediate segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
32. The antenna of claim 25 wherein:
-
the plurality of segments further includes one relatively straight intermediate segment lying in the first plane; and
the plurality of curved second segments consists of two curved second segments;
the at least two pairs of half-turn semi-circular first segments consists of two pairs of the first segments;
the one relatively straight intermediate segment lies in the first plane and is oriented such that magnetic field lines encircling the intermediate segment in a plane perpendicular thereto circulate in a direction opposite magnetic field lines encircling the first segments in the same plane; and
the segments formed of the single series conductor are arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then the intermediate segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
33. The antenna of claim 25 wherein:
-
the plurality of curved second segments consists of at least four curved second segments;
the one relatively straight intermediate segment lies in the first plane and is oriented such that magnetic field lines encircling the intermediate segment in a plane perpendicular thereto circulate in a same direction as magnetic field lines encircling the first segments in the same plane; and
the segments formed of the single series conductor are arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then a second segment, then an intermediate segment, then a second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
34. The antenna of claim 25 wherein:
-
the plurality of curved second segments consists of at least four curved second segments;
the at least two pairs of half-turn semi-circular first segments consists of two pairs of the first segments;
the one relatively straight intermediate segment lies in the first plane and is oriented such that magnetic field lines encircling the intermediate segment in a plane perpendicular thereto circulate in a same direction as magnetic field lines encircling the first segments in the same plane; and
the segments formed of the single series conductor are arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then a second segment, then the intermediate segment, then a second segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
-
35. A Faraday shield for use with an RF antenna for inductively coupling energy into a vacuum processing chamber for sustaining a high-density plasma therein comprising:
a conductive metal disc having a perimeter, a central area, and a plurality of slots therethrough circumferentially spaced around a ring in a concentric annular area between the perimeter and the central area of the disc and each slot being oriented in the annular area in a generally radial direction each separately surrounded by conductive metal of the perimeter, the central area and the annular area.
-
36. A Faraday shield for use with an RF antenna for inductively coupling energy into a vacuum processing chamber for sustaining a high-density plasma therein comprising:
-
a conductive metal disc having a plurality of slots therethrough circumferentially spaced around a ring in a concentric annular area of the disc and oriented in the annular area in a generally radial direction; and
the shield has a further plurality of slots therethrough in a central area within the annular area.
-
-
37. A method of producing a high-density, inductively coupled plasma with RF energy in a vacuum processing chamber comprising:
-
generating with a permanent magnet assembly a ring-shaped magnetic tunnel in the processing chamber adjacent a surface of a dielectric material that is in contact with a processing gas within a vacuum processing chamber;
coupling RF energy into a processing gas through the dielectric material from an RF coil isolated by the dielectric material from the processing space and having at least first segments thereof collectively forming a generally circularly-shaped ring within the magnetic tunnel proximate the dielectric material; and
energizing a ring shaped plasma in the magnetic tunnel with the coupled RF energy. - View Dependent Claims (38, 39)
coupling said RF energy through a plurality of slots in a Faraday shield located inside of the chamber, closely spaced from the dielectric material and generally parallel thereto, the shield having a plurality of slots therethrough.
-
-
39. The method of claim 37 wherein:
-
the coil is a three-dimensional coil having a plurality of segments including;
at least two pairs of half-turn semi-circular first segments arranged in a ring and lying in a first plane, the first segments being interconnected to conduct current in opposite directions, one clockwise and one counterclockwise, around the ring, and a plurality of curved second segments, each approximately one-half turn and each lying in a plane that intersects the first plane; and
the segments of the coil are formed of a single series conductor and arranged as follows;
a clockwise extending first segment, then a second segment, then a clockwise extending first segment, then at least one other segment, then a counterclockwise extending first segment, then a second segment, then a counterclockwise extending first segment.
-
Specification