Systems and methods for metastable activated radical selective strip and etch using dual plenum showerhead

The substrate processing system for selectively etching a substrate, comprising:

• a processing chamber including an upper portion in which a plasma is generated and a lower portion in which no plasma is generated;
• a first gas delivery system to supply an inert gas species to the upper portion of the processing chamber;
• a plasma generating system to generate the plasma in the upper portion of the processing chamber, the plasma including ions and metastable species;
• a second gas delivery system to supply a reactive gas species;
• a gas distribution device arranged between the upper and lower portions of the processing chamber to receive the reactive gas species, to remove ions from the plasma, to block ultraviolet (UV) light generated by the plasma and to deliver the metastable species to the lower portion of the processing chamber, wherein the gas distribution device comprises:
• at least one sidewall;
• a flange extending radially outwardly from the at least one sidewall;
• a dual gas plenum comprising:
• an upper surface and a lower surface forming an upper surface and a lower surface of the dual gas plenum;
• a gas inlet to receive the reactive gas species from the second gas delivery system;
• an annular channel formed between the upper surface and the lower surface of the dual gas plenum and connected to the gas inlet;
• a plurality of connecting channels extending between and connected to opposite sides of the annular channel;
• a first plurality of through holes extending from the connecting channels downwardly through the lower surface of the dual gas plenum to deliver the reactive gas species to the lower portion of the processing chamber;
• a second plurality of through holes in the lower surface of the dual gas plenum extending from the upper surface to the lower surface of the dual gas plenum to deliver the metastable species to the lower portion of the processing chamber;
• and
• a light blocking structure comprising at least one plate and supported by the at least one side wall, wherein the light blocking structure prevents a line of sight path between the plasma in the upper portion of the processing chamber and the substrate in the lower portion of the processing chamber, wherein the at least one plate comprises:
• a light blocking plate without through holes and including a radially outer edge that is spaced from a sidewall of the upper portion of the processing chamber;
• and
• an annular plate that is spaced from the light blocking plate and the gas distribution device, that extends to the sidewall of the upper portion of the processing chamber and that has an inner diameter that is less than an outer diameter of the light blocking plate,
• wherein the metastable species flow around the light blocking plate and through the inner diameter of the annular plate to the dual gas plenum;
• and
• a substrate support arranged below the gas distribution device in the lower portion of the processing chamber to support the substrate,
• wherein the metastable species transfer energy to the reactive gas species to selectively etch one exposed material of the substrate more than at least one other exposed material of the substrate.

A substrate processing system for selectively etching a substrate, comprising:

• a processing chamber including an upper portion in which a plasma is generated and a lower portion in which no plasma is generated;
• a first gas delivery system to supply an inert gas species to the upper portion of the processing chamber;
• a plasma generating system to generate the plasma in the upper portion of the processing chamber, the plasma including ions and metastable species;
• a second gas delivery system to supply first and second reactive gas species;
• a gas distribution device arranged between the upper and lower portions of the processing chamber to receive the first and second reactive gas species, to remove ions from the plasma, to block ultraviolet (UV) light generated by the plasma and to deliver the metastable species to the lower portion of the processing chamber, wherein the gas distribution device comprises:
• at least one sidewall;
• a flange extending radially outwardly from the at least one sidewall;
• a dual gas plenum comprising:
• an upper surface and a lower surface forming an upper surface and a lower surface of the dual gas plenum;
• a first gas inlet to receive the first reactive gas species from the second gas delivery system;
• a second gas inlet to receive the second reactive gas species from the second gas delivery system;
• a first annular channel formed adjacent to a radially outer edge of the gas distribution device and connected to the first gas inlet;
• a second annular channel formed radially inwardly from the first annular channel and connected to the second gas inlet;
• first channels connected to the first annular channel to deliver the first reactive gas species from the first gas inlet to a first plurality of locations in a first zone above the substrate, wherein a first set of the first channels extend between and are connected to opposite sides of the first annular channel, and wherein a second set of the first channels extend radially inwardly up to the second annular channel;
• second channels extending between and connected to opposite sides of the second annular channel to deliver the second reactive gas species from the second gas inlet to a second plurality of locations in a second zone above the substrate;
• a first plurality of through holes extending from the first channels downwardly through the lower surface of the dual gas plenum to deliver the first reactive gas species to the lower portion of the processing chamber;
• a second plurality of through holes extending from the second channels downwardly through the lower surface of the dual gas plenum to deliver the second reactive gas species to the lower portion of the processing chamber;
• and
• a third plurality of through holes extending from the upper surface to the lower surface of the dual gas plenum to deliver the metastable species to the lower portion of the processing chamber;
• and
• a light blocking structure comprising a plate having a fourth plurality of through holes and supported by the at least one side wall, wherein the light blocking structure prevents a line of sight path between the plasma in the upper portion of the processing chamber and the substrate in the lower portion of the processing chamber;
• and
• a substrate support arranged below the gas distribution device in the lower portion of the processing chamber to support the substrate,
• wherein the metastable species transfer energy to the first and second reactive gas species to selectively etch one exposed material of the substrate more than at least one other exposed material of the substrate.

A substrate processing system for selectively etching a substrate, comprising:

• a processing chamber including an upper portion in which a plasma is generated and a lower portion in which no plasma is generated;
• a first gas delivery system to supply an inert gas species to the upper portion of the processing chamber;
• a plasma generating system to generate the plasma in the upper portion of the processing chamber, the plasma including ions and metastable species;
• a second gas delivery system to supply first and second reactive gas species;
• a gas distribution device arranged between the upper and lower portions of the processing chamber to receive the first and second reactive gas species, to remove ions from the plasma, to block ultraviolet (UV) light generated by the plasma and to deliver the metastable species to the lower portion of the processing chamber, wherein the gas distribution device comprises:
• at least one sidewall;
• a flange extending radially outwardly from a sidewall of the gas distribution device;
• a dual gas plenum comprising:
• an upper surface and a lower surface forming an upper surface and lower surface of the dual gas plenum;
• first and second gas inlets arranged along a radially outer surface of the flange to receive the first and second reactive gas species from the second gas delivery system, respectively;
• first, second, and third channels formed respectively in the flange, the sidewall, and the lower surface of the gas distribution device, the first channel connected to the first gas inlet and to the second and third channels;
• fourth, fifth, and sixth channels formed respectively in the flange, the sidewall, and the lower surface of the gas distribution device, the fourth channel connected to the second gas inlet and to the fifth and sixth channels;
• and
• a first plurality of through holes extending from the upper surface to the lower surface to deliver the metastable species to the lower portion of the processing chamber;
• a second plurality of through holes extending from the third channels downwardly through the lower surface to deliver the first reactive gas species to the lower portion of the processing chamber;
• and
• a third plurality of through holes extending from the sixth channels downwardly through the lower surface to deliver the second reactive gas species to the lower portion of the processing chamber;
• and
• a light blocking structure comprising a plate having a fourth plurality of through holes and supported by the at least one side wall, wherein the light blocking structure prevents a line of sight path between the plasma in the upper portion of the processing chamber and the substrate in the lower portion of the processing chamber;
• and
• a substrate support arranged below the gas distribution device in the lower portion of the processing chamber to support the substrate,
• wherein the metastable species transfer energy to the first and second reactive gas species to selectively etch one exposed material of the substrate more than at least one other exposed material of the substrate.