US5405480A — Induction plasma source

Claim 1

Independent Claim 84 words

A plasma process apparatus for integrated circuit fabrication having a chamber and a platen for supporting on a surface thereof a substrate in the chamber, comprising: a hemispherically shaped induction coil having multiple windings proceeding from an equatorial base to a pole of the hemispherically shaped induction coil generally parallel to the support surface of the platen, the chamber being disposed inside the induction coil; a radio frequency power source coupled to the induction coil; and a bias power source coupled to the platen.

Claim 2

Dependent Claim 84 words

A plasma process apparatus for integrated circuit fabrication having a chamber and a platen for supporting on a surface thereof a substrate in the chamber, comprising: a hemispherically shaped induction coil having multiple windings proceeding from an equatorial base to a pole of the hemispherically shaped induction coil generally parallel to the support surface of the platen, the chamber being disposed inside the induction coil; a radio frequency power source coupled to the induction coil; and a bias power source coupled to the platen.

Claim 3

Dependent Claim 46 words

An apparatus as in claim 1, wherein the windings of the induction coil are a copper tube, further comprising a cooling system for furnishing a cooling fluid to one end of the copper tube and for removing cooling fluid from the other of the copper tube.

Claim 4

Dependent Claim 19 words

An apparatus as in claim 1 wherein the chamber is contained within a hemispherical vessel and the induction coil.

Claim 5

Dependent Claim 14 words

An apparatus as in claim 3 wherein the vessel is a quartz bell jar.

Claim 6

Dependent Claim 15 words

An apparatus as in claim 3 wherein the vessel is an aluminum oxide bell jar.

Claim 7

Dependent Claim 46 words

An apparatus as in claim 3, wherein the windings of the induction coil are a copper tube, further comprising a cooling system for furnishing a cooling fluid to one end of the copper tube and for removing cooling fluid from the other of the copper tube.

Claim 8

Dependent Claim 34 words

An apparatus as in claim 6 wherein the windings of the induction coil are packed in a thermally conductive dielectric material and the thermally conductive dielectric material couples the induction coil to the vessel.

Claim 9

Dependent Claim 19 words

An apparatus as in claim 1 wherein the bias power source is a high frequency radio frequency power source.

Claim 10

Dependent Claim 20 words

An apparatus as in claim 1 wherein the radio frequency power source is a low frequency radio frequency power source.

Claim 11

Dependent Claim 27 words

An apparatus as in claim 1 wherein a plasma is operably sustainable in the chamber generally above the platen in a pressure as low as 0.6 milliTorr.

Claim 12

Dependent Claim 110 words

A plasma process apparatus for integrated circuit fabrication having a chamber and a platen for supporting on a surface thereof a substrate in the chamber, comprising: a vessel having a hemispherical quartz wall which contains the chamber; a low frequency radio frequency power source which induces a low frequency oscillating azimuthal electric field in a region near the quartz wall so that electrons entering the region within the plasma boundary are accelerated and cancel an axial magnetic field in the interior of the plasma discharge; and a high frequency radio frequency power source which imposes a biasing voltage on the wafer independently of the low frequency radio frequency power source.

Claim 13

Dependent Claim 110 words

A plasma process apparatus for integrated circuit fabrication having a chamber and a platen for supporting on a surface thereof a substrate in the chamber, comprising: a vessel having a hemispherical quartz wall which contains the chamber; a low frequency radio frequency power source which induces a low frequency oscillating azimuthal electric field in a region near the quartz wall so that electrons entering the region within the plasma boundary are accelerated and cancel an axial magnetic field in the interior of the plasma discharge; and a high frequency radio frequency power source which imposes a biasing voltage on the wafer independently of the low frequency radio frequency power source.

Claim 14

Dependent Claim 138 words

A plasma process apparatus for integrated circuit wafer fabrication, comprising: a housing having a top plate; a bell jar having a hemispherical quartz wall, the bell jar being mounted on the top plate and containing a vacuum chamber; a platen having a top wafer-supporting surface; a hemispherical induction coil disposed about the quartz wall of the bell jar, the induction coil having a plurality of windings proceeding from an equatorial base to a pole of the hemispherically shaped induction coil generally parallel to the platen; a gas system coupled to the chamber; a radio frequency power source connected to one end of the induction coil through a matching network and the other end of the induction coil being connected to the housing; and a high frequency radio frequency power source connected to the platen through a matching network.

Claim 15

Dependent Claim 138 words

A plasma process apparatus for integrated circuit wafer fabrication, comprising: a housing having a top plate; a bell jar having a hemispherical quartz wall, the bell jar being mounted on the top plate and containing a vacuum chamber; a platen having a top wafer-supporting surface; a hemispherical induction coil disposed about the quartz wall of the bell jar, the induction coil having a plurality of windings proceeding from an equatorial base to a pole of the hemispherically shaped induction coil generally parallel to the platen; a gas system coupled to the chamber; a radio frequency power source connected to one end of the induction coil through a matching network and the other end of the induction coil being connected to the housing; and a high frequency radio frequency power source connected to the platen through a matching network.

Claim 16

Dependent Claim 32 words

An apparatus as in claim 12 wherein the windings of the induction coil form a single hemispherically shaped expanding spiral layer having an internal volume sufficiently large to contain the bell jar.

Claim 17

Dependent Claim 36 words

An apparatus as in claim 12 wherein the windings of the induction coil are a copper tube, further comprising a cooling system for circulating a cooling fluid through the copper tube to cool the induction coil.

Claim 18

Dependent Claim 35 words

An apparatus as in claim 14 wherein the windings of the induction coil are packed in a thermally conductive dielectric material and the thermally conductive dielectric material couples the induction coil to the bell jar.

Claim 19

Dependent Claim 26 words

An apparatus as in claim 12 wherein a plasma is operably sustainable in the vacuum chamber at a gas pressure therein as low as 0.6 milliTorr.

Claim 20

Dependent Claim 26 words

An apparatus as in claim 12 wherein a plasma is operably sustainable in the vacuum chamber at a gas pressure therein as low as 0.1 milliTorr.

Claim 21

Independent Claim 64 words

A method of generating a plasma for processing an integrated circuit substrate comprising the steps of: placing the substrate in a chamber contained within a hemispherical induction coil; delivering a gas to the chamber; applying an oscillating current to the induction coil so that a plasma is formed by excitation of the gas in the chamber; and imposing a biasing voltage on the substrate.

Claim 22

Independent Claim 64 words

A method of generating a plasma for processing an integrated circuit substrate comprising the steps of: placing the substrate in a chamber contained within a hemispherical induction coil; delivering a gas to the chamber; applying an oscillating current to the induction coil so that a plasma is formed by excitation of the gas in the chamber; and imposing a biasing voltage on the substrate.

Claim 23

Dependent Claim 24 words

A method as in claim 18 further comprising the step of sustaining in the chamber a gas pressure therein as low as 1.0 milliTor.

Claim 24

Dependent Claim 44 words

A method as in claim 18 wherein: the imposing step includes the step of applying a high frequency radio frequency power source to the substrate; and the applying step includes the step of applying a low frequency radio frequency power source to the coil.

Claim 25

Dependent Claim 40 words

A method as in claim 18 wherein: the plasma process is an ion sputter process; and the delivering step includes delivering an inert gas to the chamber at low pressure to remove material from the substrate surface by momentum transfer.

Claim 26

Dependent Claim 39 words

A method as in claim 18, wherein: the plasma process is a chemical etching procedure; and the delivering step includes delivering a reactive gas at a high pressure to the substrate from multiple gas sources arranged radially symmetrical thereabout.

Claim 27

Dependent Claim 30 words

A method as in claim 18, wherein: the plasma process is a plasma-enhanced chemical vapor deposition (PECVD) procedure; and the delivering step includes delivering a reactive gas to the substrate.

Claim 28

Dependent Claim 22 words

A method as in claim 23, wherein the delivering step includes delivering the reactive gas at a high pressure to the substrate.

Claim 29

Dependent Claim 26 words

A method as in claim 23, wherein the delivering step includes delivering the reactive gas to the substrate from multiple gas sources arranged radially symmetrical thereabout.

Claim 30

Dependent Claim 26 words

A method as in claim 18, further comprising the step of evacuating the chamber to a pressure less than atmospheric pressure prior to the delivering step.

Claim 31

Dependent Claim 29 words

A method as in claim 18, wherein the induction coil is a copper tube and the method further comprises the step of circulating a cooling fluid through the tube.

Claim 32

Dependent Claim 24 words

A method as in claim 27 further comprising the step of packing the windings of the induction coil in a thermally conductive dielectric material.

Claim 33

Dependent Claim 29 words

A method as in claim 27 wherein the chamber is contained within a hemispherical vessel and the thermally conductive dielectric material couples the induction coil to the bell jar.

Claim 34

Dependent Claim 80 words

A chamber housing of a plasma process apparatus for integrated circuit fabrication, comprising: a vessel disposed about a chamber; an induction coil disposed about the vessel and having multiple windings of a copper tube; a cooling system furnishing a cooling fluid to one end of the copper tube and removing cooling fluid from the other of the copper tube; and a thermally conductive dielectric material packing the windings of the induction coil and coupling the induction coil to the vessel.

Claim 35

Dependent Claim 80 words

A chamber housing of a plasma process apparatus for integrated circuit fabrication, comprising: a vessel disposed about a chamber; an induction coil disposed about the vessel and having multiple windings of a copper tube; a cooling system furnishing a cooling fluid to one end of the copper tube and removing cooling fluid from the other of the copper tube; and a thermally conductive dielectric material packing the windings of the induction coil and coupling the induction coil to the vessel.

Claim 36

Dependent Claim 38 words

A housing as in claim 29 wherein the vessel and the induction coil are hemispherically shaped and the multiple windings of the induction coil wind from an equatorial base to a pole of the hemispherically shaped induction coil.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1998-04-10	1998-10-10	1999-04-11	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2002-04-10	2002-10-10	2003-04-11	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2006-04-10	2006-10-10	2007-04-11	$7700.00	Window Closed / Lapsed

Induction plasma source

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag