US4397724A — Apparatus and method for plasma-assisted etching …

Claim 1

Independent Claim 49 words

Apparatus for plasma-assisted dry etching of a layer formed on a wafer, said apparatus comprising a reaction chamber, means for establishing an etching plasma within said chamber, said chamber including surfaces exposed to said plasma, and a covering of a polyarylate polymer on at least some of said surfaces.

Claim 2

Dependent Claim 49 words

Apparatus for plasma-assisted dry etching of a layer formed on a wafer, said apparatus comprising a reaction chamber, means for establishing an etching plasma within said chamber, said chamber including surfaces exposed to said plasma, and a covering of a polyarylate polymer on at least some of said surfaces.

Claim 3

Dependent Claim 26 words

An apparatus as in claim 1 wherein said polymer is selected from the group consisting of Ardel 100, Ardel 203, and Ardel 205, Ardel 208, U-Polymer.

Claim 4

Dependent Claim 28 words

An apparatus as in claim 2 further including a cathode electrode in said reaction chamber, and means including polyarylate polymer-covered surfaces mounting said wafer on said cathode electrode.

Claim 5

Dependent Claim 38 words

An apparatus as in claim 3 wherein said wafer includes a layer of aluminum to be etched, and wherein said establishing means includes means for introducing a mixture of boron trichloride and chlorine gases into said reaction chamber.

Claim 6

Dependent Claim 38 words

An apparatus as in claim 3 wherein said wafer includes a layer of polysilicon to be etched, and wherein said establishing means includes means for introducing a mixture of boron trichloride and chlorine gases into said reaction chamber.

Claim 7

Dependent Claim 34 words

An apparatus as in claim 3 wherein said wafer includes a layer of polysilicon to be etched, and wherein said establishing means includes means for introducing essentially pure chlorine gas into said reaction chamber.

Claim 8

Dependent Claim 38 words

An apparatus as in claim 3 wherein said wafer includes a layer of silicon dioxide to be etched, and wherein said establishing means includes means for introducing a mixture of trifluoromethane and ammonia gases into said reaction chamber.

Claim 9

Dependent Claim 36 words

An apparatus as in claim 3 wherein said wafer includes a layer of hardened resist material to be etched, and wherein said establishing means includes means for introducing a halocarbon and/or oxygen into said reaction chamber.

Claim 10

Dependent Claim 56 words

An apparatus as in claim 3 wherein said wafer includes a layer of tantalum disilicide to be etched, and wherein said establishing means includes means for introducing into said reaction chamber a gas from whch are derived active etchant radicals that include fluorine and chlorine constituents as the predominant etchant species for tantalum and silicon, respectively.

Claim 11

Dependent Claim 98 words

An apparatus as in claim 4 wherein said establishing means includes means for establishing the following conditions in said reaction chamber: a pressure of approximately 20 micrometers, a power density of approximately 0.15 watts per square centimeter at the surface of the layer to be etched, a gas flow into said chamber of approximately 75 volume percent boron trichloride and 25 volume percent chlorine, a gas flow into said chamber of approximately 75 cubic centimeters per minute and a dc bias voltage of said cathode electrode with respect to a point of reference potential of approximately 210 volts.

Claim 12

Dependent Claim 80 words

An apparatus as in claim 6 wherein said establishing means includes means for establishing the following conditions in said reaction chamber: a pressure of approximately 10 micrometers, a power density of approximately 0.1 watts per square centimeters at the surface of the layer to be etched, a gas flow into said chamber of approximately 40 cubic centimeters per minute and a dc bias voltage of said cathode electrode with respect to a point of reference potential of approximately 300 volts.

Claim 13

Dependent Claim 97 words

An apparatus as in claim 7 wherein said establishing means includes means for establishing the following conditions in said reaction chamber: a pressure of approximately 50 micrometers, a power density of approximately 0.16 watts per square, centimeter at the surface of the layer to be etched, a gas flow into said chamber of approximately 96 volume percent trifluoromethane and 4 volume percent ammonia, a gas flow into said chamber of approximately 30 cubic centimeters per minute and a dc bias voltage of said cathode electrode with respect to a point of reference potential of approximately 600 volts.

Claim 14

Dependent Claim 98 words

Apparatus for plasma-assisted dry etching of a layer on a wafer that is to be processed to form multiple integrated circuits, said apparatus comprising a reaction chamber, means for establishing an etching plasma within said chamber, means within said chamber for holding a number of wafers to be etched, said chamber having internal surfaces including surfaces of said holding means in the immediate vicinity of said wafers to be etched, and a layer of a high-temperature-tolerant polyarylate polymer formed on internal surfaces including at least the surfaces of said holding means in the immediate vicinity of said wafers.

Claim 15

Dependent Claim 98 words

Apparatus for plasma-assisted dry etching of a layer on a wafer that is to be processed to form multiple integrated circuits, said apparatus comprising a reaction chamber, means for establishing an etching plasma within said chamber, means within said chamber for holding a number of wafers to be etched, said chamber having internal surfaces including surfaces of said holding means in the immediate vicinity of said wafers to be etched, and a layer of a high-temperature-tolerant polyarylate polymer formed on internal surfaces including at least the surfaces of said holding means in the immediate vicinity of said wafers.

Claim 16

Dependent Claim 18 words

Apparatus as in claim 13 wherein said plasma is derived from a mixture of boron trichloride and chlorine.

Claim 17

Dependent Claim 14 words

Apparatus as in claim 13 wherein said plasma is derived from essentially pure chlorine.

Claim 18

Dependent Claim 17 words

Apparatus as in claim 13 wherein said plasma is derived from a mixture of trifluoromethane and ammonia.

Claim 19

Dependent Claim 17 words

Apparatus as in claim 13 wherein said plasma is derived from oxygen or a halocarbon and oxygen.

Claim 20

Dependent Claim 36 words

Apparatus as in claim 13 wherein said establishing means includes means for introducing into said reaction chamber a gas from which are derived active etchant radicals that include fluorine and chlorine as the predominant etchant species.

Claim 21

Independent Claim 63 words

A method for fabricating VLSI devices by delineating fine-line patterns on a wafer in accordance with a process sequence that includes plasma-assisted dry etching, said method comprising the steps of mounting said wafer to be etched in a reaction chamber at least some of whose surfaces are covered with a layer of a polyarylate polymer, and establishing an etching plasma within said chamber.

Claim 22

Independent Claim 63 words

A method for fabricating VLSI devices by delineating fine-line patterns on a wafer in accordance with a process sequence that includes plasma-assisted dry etching, said method comprising the steps of mounting said wafer to be etched in a reaction chamber at least some of whose surfaces are covered with a layer of a polyarylate polymer, and establishing an etching plasma within said chamber.

Claim 23

Dependent Claim 26 words

A method as in claim 19 wherein said polymer is selected from the group consisting of Ardel 100, Ardel 203, Ardel 205, Ardel 208 and U-Polymer.

Claim 24

Dependent Claim 28 words

A method as in claim 20 wherein a cathode electrode is included in said reaction chamber and said wafer to be etched is mounted on said cathode electrode.

Claim 25

Dependent Claim 35 words

A method as in claim 21 wherein said wafer includes a layer of aluminum to be etched, and wherein said establishing step includes introducing a mixture of boron trichloride and chlorine gases into said chamber.

Claim 26

Dependent Claim 35 words

A method as in claim 21 wherein said wafer includes a layer of polysilicon to be etched, and wherein said establishing step includes introducing a mixture of boron trichloride and chlorine gases into said chamber.

Claim 27

Dependent Claim 31 words

A method as in claim 21 wherein said wafer includes a layer of polysilicon to be etched, and wherein said establishing step includes introducing essentially pure chlorine gas into said chamber.

Claim 28

Dependent Claim 35 words

A method as in claim 21 wherein said wafer includes a layer of silicon dioxide to be etched, and wherein said establishing step includes introducing a mixture of trifluoromethane and ammonia gases into said chamber.

Claim 29

Dependent Claim 33 words

A method as in claim 21 wherein said wafer includes a layer of hardened resist material to be etched, and wherein said establishing step includes introducing a halocarbon and/or oxygen into said chamber.

Claim 30

Dependent Claim 53 words

A method as in claim 21 wherein said wafer includes a layer of tantalum disilicide to be etched, and wherein said establishing step includes introducing into said chamber a gas from which are derived active etchant radicals that include fluorine and chlorine constituents as the predominant etchant species for tantalum and silicon, respectively.

Claim 31

Dependent Claim 95 words

A method as in claim 22 wherein said establishing step includes establishing the following conditions within said chamber: a pressure of approximately 20 micrometers, a power density of approximately 0.15 watts per square centimeter at the surface of the layer to be etched, a gas flow into said chamber of approximately 75 volume percent boron trichloride and 25 volume percent chlorine, a gas flow into said chamber of approximately 75 cubic centimeters per minute and a dc bias voltage of said cathode electrode with respect to a point of reference potential of approximately 210 volts.

Claim 32

Dependent Claim 77 words

A method as in claim 24 wherein said establishing step includes establishing the following conditions within said chamber: a pressure of approximately 10 micrometers, a power density of approximately 0.1 watts per square centimeter at the surface of the layer to be etched, a gas flow into said chamber of approximately 40 cubic centimeters per minute and a dc bias voltage of said cathode electrode with respect to a point of reference potential of approximately 300 volts.

Claim 33

Dependent Claim 94 words

A method as in claim 25 wherein said establishing step includes establishing the following conditions within said chamber: a pressure of approximately 50 micrometers, a power density of approximately 0.16 watts per square centimeter at the surface of the layer to be etched, a gas flow into said chamber of approximately 96 volume percent trifluoromethane and 4 volume percent ammonia, a gas flow into said chamber of approximately 30 cubic centimeters per minute and a dc bias voltage of said cathode electrode with respect to a point of reference potential of approximately 600 volts.

Claim 34

Dependent Claim 48 words

Apparatus for plasma-assisted dry etching of a layer formed on a wafer, said apparatus comprising a reaction chamber, means for establishing an etching plasma within said chamber, said chamber including surfaces exposed to said plasma, and a covering of Ekonol Polymer on at least some of said surfaces.

Claim 35

Dependent Claim 48 words

Apparatus for plasma-assisted dry etching of a layer formed on a wafer, said apparatus comprising a reaction chamber, means for establishing an etching plasma within said chamber, said chamber including surfaces exposed to said plasma, and a covering of Ekonol Polymer on at least some of said surfaces.

Claim 36

Independent Claim 62 words

A method for fabricating VLSI devices by delineating fine-line features on a wafer in accordance with a process sequence that includes plasma-assisted dry etching, said method comprising the steps of mounting said wafer to be etched in a reaction chamber at least some of whose surfaces are covered with a layer of Ekonol Polymer, and establishing an etching plasma within said chamber.

Claim 37

Independent Claim 62 words

A method for fabricating VLSI devices by delineating fine-line features on a wafer in accordance with a process sequence that includes plasma-assisted dry etching, said method comprising the steps of mounting said wafer to be etched in a reaction chamber at least some of whose surfaces are covered with a layer of Ekonol Polymer, and establishing an etching plasma within said chamber.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1986-08-08	1987-02-07	1987-08-09	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1990-08-08	1991-02-07	1991-08-09	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1994-08-08	1995-02-07	1995-08-09	$7700.00	Window Closed / Lapsed

Apparatus and method for plasma-assisted etching of wafers

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