Apparatus and method for downstream pressure control and sub-atmospheric reactive gas abatement

• US 20070012402A1
• Filed: 07/08/2004
• Published: 01/18/2007
• Est. Priority Date: 07/08/2003
• Status: Abandoned Application

• Current Assignee: Sundew Technologies LLC
• Original Assignee: Sundew Technologies LLC
• Inventors: Sneh, Ofer
• Application Number:
  US10/563,519
• Publication Number:
  US 20070012402A1
• Time in Patent Office: Days
• US Class Current: 156/345.290
• CPC Class Codes: C23C 16/4412 Details relating to the exhausts, e.g. pumps, filters, scrubbers, particle traps
• CPC Class Codes: C23C 16/45557 Pulsed pressure or control pressure
• CPC Class Codes: Y10T 137/0396 Involving pressure control

Abstract

A sub-atmospheric downstream pressure control apparatus (200) includes a first flow restricting element (FRE) (202); a pressure control chamber (PCC) (204) located in serial fluidic communication downstream from the first FRE; a second FRE (206) located in serial fluidic communication downstream from the PCC; a gas source (208); and a flow controlling device (210) in serial fluidic communication downstream from the gas source and upstream from the PCC.

Claims

1. A sub-atmospheric downstream pressure control apparatus (200), characterized by:

a first flow restricting element (FRE)(202);

a pressure control chamber (PCC) (204) located in serial fluidic communication downstream from said first FRE;

a second FRE (206) located in serial fluidic communication downstream from said PCC;

a gas source (208); and

a flow controlling device (210) in serial fluidic communication downstream from said gas source and upstream from said PCC.

2. A sub-atmospheric downstream pressure control apparatus as in claim 1 further characterized by:

a reactive gas source (422) connected in serial fluidic communication upstream from said PCC; and

an abatement element (420) located within said PCC.

3. A sub-atmospheric downstream pressure control apparatus as in claim 1 further characterized by:

a third FRE (504) connected in serial fluidic communication downstream from said PCC;

an abatement chamber (502) connected in serial fluidic communication downstream from said third FRE;

a reactive gas source (506) connected in serial fluidic communication upstream from said abatement chamber; and

an abatement element (520) disposed within said abatement chamber.

4. A sub-atmospheric downstream pressure control apparatus as in claim 1 wherein a process chamber (304) is located in serial fluidic communication upstream from said first FRE;

said process chamber and said PCC (308) are formed as compartments within a single process vessel (324); and

said first FRE (306) is formed within the partition between said process chamber and said PCC.

5. A wafer processing apparatus comprising a process chamber (10), said apparatus characterized by;

a process reactive gas supply line (12) from a process gas source in serial fluidic communication upstream from said process chamber;

an upstream flow control device located in serial fluidic communication upstream from said process chamber and downstream from said process gas source;

a first flow restricting element (202) located in serial fluidic communication downstream from said process chamber;

a pressure control chamber (PCC) (204) located in serial fluidic communication downstream from said first FRE;

a second FRE (206) located in serial fluidic communication downstream from said PCC;

a gas source (208); and

a flow controlling device (210) in serial fluidic communication downstream from said gas source and upstream from said PCC.

6. A sub-atmospheric downstream pressure control apparatus as in claim 5 further characterized by:

a reactive gas source (422) connected in serial fluidic communication upstream from said PCC; and

an abatement element (420) located within said PCC.

7. A sub-atmospheric downstream pressure control apparatus as in claim 5 further characterized by:

a third FRE (504) connected in serial fluidic communication downstream from said PCC (200);

an abatement chamber (500) connected in serial fluidic communication upstream from said third FRE;

a reactive gas source (506) connected in serial fluidic communication upstream from said abatement chamber; and

an abatement element (520) located within said abatement chamber.

8. A sub-atmospheric downstream pressure control apparatus as in claim 5 wherein a process chamber (304) is located in serial fluidic communication upstream from said first FRE (306);

said process chamber and said PCC (308) are formed as compartments within a single process vessel (324); and

said first FRE is formed within the partition between said process chamber and said PCC.

9. A sub-atmospheric downstream pressure control apparatus as in claim 5 wherein said process is LPCVD.

10. A sub-atmospheric downstream pressure control apparatus as in claim 5 wherein said process is RIE.

11. A sub-atmospheric downstream pressure control apparatus as in claim 5 wherein said process is PECVD.

12. A downstream pressure control method, comprising controlling a flow of process gas into a process chamber;

said method characterized by;

providing a flow of gas into a pressure control chamber (PCC) connected in serial fluidic communication downstream from said process chamber;

controlling fluid flow with a first flow restricting element (FRE) located in serial fluidic communication downstream from said process chamber and upstream from said PCC; and

controlling the pressure at said process chamber by adjusting the pressure in said PCC to impact the pressure gradient over said first flow restricting element.

13. A method for sub-atmospheric reactive gas abatement, characterized by:

providing a substantial pressure gradient at an inlet to an abatement space;

providing a substantial pressure gradient at an outlet from said abatement space;

flowing a reactive abatement gas into said abatement space;

reacting with process gas exhaust effluents to produce substantially stable and inert solid; and

substantially localizing said substantially stable and inert solid within said abatement chamber.

14. A method for sub-atmospheric reactive gas abatement of process gas exhaust effluent, said method characterized by:

providing a substantial pressure gradient at an inlet to an abatement space;

providing a substantial pressure gradient at an outlet from said abatement space;

flowing a reactive abatement gas into said abatement space;

reacting said reactive abatement gas with said process gas exhaust effluent to produce a substantially volatile effluent gas; and

transporting said substantially volatile effluent gas through a pump foreline and pump substantially without further reaction and substantially without growth of film deposits.

15. A wall-protected process chamber (710, 730), comprising:

an external enclosure (602);

a gas permeable internal enclosure (604) disposed within said external metallic enclosure and enclosing said process chamber;

a seal (608, 610) between said internal enclosure and said external metallic enclosure, said internal enclosure and said external enclosure defining a substantially sealed space (606) between the outer wall of said internal enclosure and the inner wall of said external metallic enclosure; and

a source (612) of a pressurized inert gas in fluid communication with said sealed space;

whereby said pressurized inert gas flows through said gas permeable internal enclosure to protect said process chamber wall.