Plasma sputter etching system with reduced particle contamination

Claim 1

A plasma processing system for plasma sputter etching a substrate with reduced particle contamination comprising: a plasma processing chamber having an interior surface to define a processing space therein to contain a substrate to be sputter etched and including a vacuum system for creating a vacuum environment in said processing space; an electrical element coupled to the plasma processing chamber for coupling electrical energy into at least a portion of the processing space through the interior surface for generating a plasma therein to etch the substrate which thereby produces a temperature rise in the processing chamber interior surface up to a processing temperature, the element being operable for interrupting the electrical energy to the processing space so that the plasma is extinguished when the plasma processing is complete; a heating device coupled to the plasma processing chamber externally of the vacuum processing space and operable for controllably heating the processing chamber interior surface; a temperature control circuit connected to the heating device to control the operation and temperature of the heating device, the temperature control circuit turning the heating device to an ON state and operating the heating device for heating the processing chamber interior surface to approximately said processing temperature approximately at the time when the electrical element is interrupting energy to the processing chamber and the plasma is being extinguished, the temperature of the chamber interior space, after plasma generation, being maintained by the temperature control circuit approximately at the processing temperature of the processing chamber interior space during plasma generation, such that the chamber interior surface is maintained at a relatively constant temperature during plasma processing and for a predetermined time before and thereafter to prevent the flaking of deposited sputtered material from the processing chamber interior surface and the generation of contamination particles within the processing space; whereby contamination of the sputter etched substrate is reduced.

Claim 14

A method of sputter etching a substrate with a plasma with reduced particle contamination of the substrate, comprising: positioning a substrate within a processing space of a plasma processing chamber, the chamber having an interior surface surrounding a portion of the processing space; creating a vacuum environment in the processing space; introducing a plasma gas into the processing chamber; coupling electrical energy with an electrical element through the interior surface and into at least a portion of the processing space and the plasma gas for generating a plasma therein to etch the substrate wherein the interior surface is heated to a processing temperature, and subsequently interrupting the flow of energy to the processing space so that the plasma is extinguished when plasma processing is complete; controllably heating the plasma processing chamber with a heating device externally of the vacuumed processing space to maintain said interior surface at approximately the processing temperature approximately at the time when energy to the processing space is interrupted and the plasma is being extinguished, the temperature of the interior surface of the chamber, after plasma generation, being maintained at approximately said processing temperature of the chamber during plasma generation such that the processing chamber interior surface is maintained at a relatively constant temperature during plasma processing and for a predetermined time before and thereafter to prevent the flaking of deposited sputtered material from the processing chamber interior surface and the generation of contamination particles within the processing space; whereby contamination of the sputter etched surface is reduced.

Claim 15

A method of sputter etching a substrate with a plasma with reduced particle contamination of the substrate, comprising: positioning a substrate within a processing space of a plasma processing chamber, the chamber having an interior surface surrounding a portion of the processing space; creating a vacuum environment in the processing space; introducing a plasma gas into the processing chamber; coupling electrical energy with an electrical element through the interior surface and into at least a portion of the processing space and the plasma gas for generating a plasma therein to etch the substrate wherein the interior surface is heated to a processing temperature, and subsequently interrupting the flow of energy to the processing space so that the plasma is extinguished when plasma processing is complete; controllably heating the plasma processing chamber with a heating device externally of the vacuumed processing space to maintain said interior surface at approximately the processing temperature approximately at the time when energy to the processing space is interrupted and the plasma is being extinguished, the temperature of the interior surface of the chamber, after plasma generation, being maintained at approximately said processing temperature of the chamber during plasma generation such that the processing chamber interior surface is maintained at a relatively constant temperature during plasma processing and for a predetermined time before and thereafter to prevent the flaking of deposited sputtered material from the processing chamber interior surface and the generation of contamination particles within the processing space; whereby contamination of the sputter etched surface is reduced.