Symmetric tunable inductively coupled HDP-CVD reactor

• US 6,170,428 B1
• Filed: 07/15/1996
• Issued: 01/09/2001
• Est. Priority Date: 07/15/1996
• Status: Expired due to Term

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Maydan, Dan, Wong, Yaxin, Wong, Manus, Redeker, Fred C., Hanawa, Hiroji, Ishikawa, Tetsuya, Lue, Brian, Steger, Robert J., Li, Shijian, Moghadam, Farhad, Sinha, Ashok K.
• Primary Examiner(s): Dang, Thi
• Assistant Examiner(s): ALEJANDRO MULERO, LUZ L
• Application Number:
  US08/679,927
• Time in Patent Office: 1,639 Days
• Field of Search: 118/723.I, 118/723.IR, 118/723.AN, 118/715, 156/345, 134/1.1, 315/111.51
• US Class Current: 118/723.00I
• CPC Class Codes: C23C 16/507 using external electrodes, e.g. in tunnel type reactors
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow
• CPC Class Codes: H01J 37/32467 Material
• CPC Class Codes: H01J 37/32522 Temperature
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts

Abstract

The present invention provides an HDP-CVD tool using simultaneous deposition and sputtering of doped and undoped silicon dioxide capable of excellent gap fill and blanket film deposition on wafers having sub 0.5 micron feature sizes having aspect ratios higher than 1.2:1. The system of the present invention includes: a dual RF zone inductively coupled plasma source configuration capable of producing radially tunable ion currents across the wafer; a dual zone gas distribution system to provide uniform deposition properties across the wafer surface; temperature controlled surfaces to improve film adhesion and to control extraneous particle generation; a symmetrically shaped turbomolecular pumped chamber body to eliminate gas flow or plasma ground azimuthal asymmetries; a dual helium cooling zone electrostatic chuck to provide and maintain uniform wafer temperature during processing; an all ceramic/aluminum alloy chamber construction to eliminate chamber consumables; and a remote fluorine based plasma chamber cleaning system for high chamber cleaning rate without chuck cover plates.

Claims

1. An apparatus for processing semiconductor substrates, comprising:

a) an enclosure comprising a sidewall and a lid, the sidewall having a first end and a second end, and the lid connected to the first end of the sidewall;

b) a substrate support member cantilever mounted on the sidewall of the enclosure, the support member having a substrate supporting surface located thereon;

c) a first gas distribution outlet positioned circumferentially about an interior surface of the sidewall between the lid and the substrate supporting surface;

d) a second gas distribution outlet disposed through the lid;

e) an exhaust port connected to the second end of the sidewall;

f) a first RF coil disposed on an exterior surface of the lid; and

g) a first frequency-tuning RF power source connected to the first RF coil.

2. The apparatus of claim 1 wherein the frequency-tuning RF power source is adapted to change frequency of the RF power source in response to reflected power.

3. The apparatus of claim 1 wherein the lid comprises a material selected from the group consisting of a ceramic dielectric material, aluminum oxide and aluminum nitride.

4. The apparatus of claim 1, further comprising:

h) a second RF coil disposed on an exterior surface of the lid; and

i) a second frequency-tuning RF power source connected to the second RF coil.

5. The apparatus of claim 4, further comprising:

j) a first RF matching network for matching the first RF power supply to the first RF coil and a second RF matching network for matching the second RF power supply to the second RF coil.

6. The apparatus of claim 5 wherein each RF matching network comprises a matching network selected from the group consisting of:

a pi impedance matching network, a balanced antenna impedance matching network, and a grounded antenna matching network.

7. The apparatus of claim 4 wherein each frequency tuning RF power source includes a control circuit adapted to adjust a frequency of the RF power source to respond to changes in reflected power.

8. The apparatus of claim 1 wherein the first RF coil comprises a concentrically wound helical coil disposed above the lid.

10. The apparatus of claim 1 wherein the substrate supporting member comprises an electrostatic chuck having an RF bias power connected thereto.

11. The apparatus of claim 10, wherein the substrate support member includes a dual zone substrate backside gas distribution system disposed on a substrate receiving surface for controlling substrate temperature.

12. The apparatus of claim 10 further comprising:

h) a substrate RF power supply and a substrate RF matching network coupling RF power to the substrate supporting surface.

13. The apparatus of claim 12 wherein the substrate RF matching network comprises a matching network selected from the group consisting of:

a pi impedance matching network, a balanced antenna impedance matching network, and a grounded antenna matching network.

14. The apparatus of claim 1, further comprising:

h) a cleaning gas feed port disposed on the enclosure connectable to a remote cleaning plasma source; and

i) one or more cleaning gas inlets defined within the enclosure sidewall connected to the cleaning gas feed port.

15. The apparatus of claim 14 wherein the remote cleaning plasma source comprises a microwave plasma generator.

16. The apparatus of claim 1 wherein the exhaust port tapers from the second end of the sidewall to a flange of an exhaust pumping stack.

17. The apparatus of claim 16 wherein the pumping stack comprises a throttle assembly connected to the exhaust port, a valve connected to the throttle assembly and a vacuum pump connected to the valve.

18. The apparatus of claim 17 wherein the exhaust port and the pumping stack are disposed substantially axially below the substrate support member.

19. The apparatus of claim 1, further comprising:

h) a heater plate and a cold plate disposed on the chamber lid.

9. The apparatus of claim wherein the second RF coil comprises an axially wound helical coil disposed around the lid.

20. A method for processing a substrate, comprising:

a) positioning the substrate on a substrate support member that is cantilever mounted on a sidewall of a processing chamber;

b) introducing a first gas through a first gas distribution system positioned circumferentially about an interior surface of the sidewall between a chamber lid and the substrate support member;

c) introducing a second gas through a second gas distribution system disposed through the lid;

d) generating a plasma of the first and second gases introduced into the chamber using a first frequency-tuning RF power source connected to a first RF coil disposed on an exterior surface of the lid and a second frequency-tuning RF power source connected to a second coil disposed on an exterior surface of the lid, whereby a process selected from the group comprising deposition and etching is performed on the substrate; and

e) exhausting the gases through an exhaust port connected on an end opposite of the lid.

21. The method of claim 20, further comprising:

f) controlling a temperature of the substrate disposed on the substrate support member using a dual zone substrate backside gas distribution system disposed on a substrate receiving surface.

22. The method of claim 21, further comprising:

f) removing the substrate from the chamber; and

g) cleaning the chamber using a plasma supplied from a remote plasma source.

23. The method of claim 22 wherein the remote plasma source supplies excited fluorine atoms from a cleaning gas selected from the group consisting of NF₃, F₂, SF₆, and ClF₃.

24. The method of claim 23 wherein the excited fluorine atoms in the cleaning gas are diluted with argon gas to a concentration between about 10% and about 50%.

25. The method of claim 20, further comprising:

f) varying a frequency of the RF power sources to respond to changes in reflected power.

26. The method of claim 20, further comprising:

f) controlling a temperature of the chamber lid.