Apparatus including gas distribution member supplying process gas and radio frequency (RF) power for plasma processing
AssigneeLam Research Corporation
InventorsRajinder Dhindsa, Eric Lenz
Life of this patent
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Abstract
A plasma processing apparatus includes a gas distribution member which supplies a process gas and radio frequency (RF) power to a showerhead electrode. The gas distribution member can include multiple gas passages which supply the same process gas or different process gases at the same or different flow rates to one or more plenums at the backside of the showerhead electrode. The gas distribution member provides a desired process gas distribution to be achieved across a semiconductor substrate processed in a gap between the showerhead electrode and a bottom electrode on which the substrate is supported.
Claims17
A method of controlling plasma etching, comprising:
- heating a showerhead electrode in a plasma etching chamber at a temperature of at least 80° C.;
- supplying process gas comprising a fluorocarbon and/or hydrofluorocarbon gas to a plasma etching chamber through the showerhead electrode, the process gas flowing into a gap between the showerhead electrode and a bottom electrode on which a semiconductor substrate is supported;
- and
- etching the semiconductor substrate in the plasma etching chamber by applying RF power to the showerhead electrode and energizing the process gas into a plasma state,
- wherein
- the heating of the showerhead electrode reduces striations on a photoresist on the semiconductor substrate by controlling fluorine radical density in the process gas;
- the RF power and the process gas are supplied to the showerhead electrode by a gas distribution member electrically isolated from other parts of the plasma etching chamber;
- and
- supplying gas comprises supplying gas from the gas distribution member to one or more plenums at the backside of the showerhead electrode.
A method of controlling plasma etching, comprising:
- heating a showerhead electrode in a plasma etching chamber at a temperature of at least 80° C.,
- supplying process gas to a plasma etching chamber through the showerhead electrode, the process gas flowing into a gap between the showerhead electrode and a bottom electrode on which a semiconductor substrate is supported, and
- etching the semiconductor substrate in the plasma etching chamber by applying RF power to the showerhead electrode and energizing the process gas into a plasma state;
- wherein
- the RF power and the process gas are supplied to the showerhead electrode by a gas distribution member electrically isolated from other parts of the plasma etching chamber;
- supplying gas comprises supplying gas from the gas distribution member to one or more plenums at the backside of the showerhead electrode;
- and
- the gas distribution member includes
- a first portion adapted to extend axially into an opening in a temperature controlled top wall of the plasma processing chamber, and
- a second portion extending laterally over the showerhead electrode, the second portion providing a RF path to multiple contact points across the showerhead electrode;
- wherein
- the multiple contact points provide laterally spaced thermal paths extending axially between upper and lower surfaces of the second portion, and
- the gas distribution member includes first and second axially extending gas passages operable to supply process gas to discrete and annular plenums between the backside of the showerhead electrode and the gas distribution member, wherein the first axially extending gas passage is adapted to connect a first gas supply to the central plenum and the second axially extending gas passage is adapted to connect a second gas supply to the annular plenum.
Dependencies are inferred from the claim text.