UV-ASSISTED REACTIVE ION ETCH FOR COPPER

• US 20140262755A1
• Filed: 03/09/2014
• Published: 09/18/2014
• Est. Priority Date: 03/13/2013
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Ren, He, Deshmukh, Subhash, Liu, Jingjing
• Application Number:
  US14/201,892
• Publication Number:
  US 20140262755A1
• Time in Patent Office: Days
• US Class Current: 204/192.35
• CPC Class Codes: C23F 4/00 Processes for removing metallic material from surfaces, not provided for in group C23F1/00 or C23F3/00
• CPC Class Codes: H01J 2237/334 Etching
• CPC Class Codes: H01J 37/32128 using particular waveforms, e.g. polarised waves
• CPC Class Codes: H01J 37/32146 Amplitude modulation, includes pulsing
• CPC Class Codes: H01J 37/32155 Frequency modulation
• CPC Class Codes: H01J 37/32431 Constructional details of the reactor
• CPC Class Codes: H01J 37/32724 Temperature
• CPC Class Codes: H01L 21/02057 Cleaning during device manufacture
• CPC Class Codes: H01L 21/0206 during, before or after processing of insulating layers
• CPC Class Codes: H01L 21/02068 during, before or after processing of conductive layers, e.g. polysilicon or amorphous silicon layers
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching
• CPC Class Codes: H01L 21/67115 mainly by radiation

Abstract

In some embodiments, a plasma etching apparatus is provided for etching copper that includes (1) a chamber body having a process chamber adapted to receive a substrate; (2) an RF source coupled to an RF electrode; (3) a pedestal located in the processing chamber and adapted to support a substrate; and (4) a UV source configured to delivery UV light to the processing chamber during at least a portion of an etch process performed within the plasma etching apparatus. Numerous other aspects are provided.

Claims

1. A plasma etching apparatus for etching copper, comprising:

a chamber body having a process chamber adapted to receive a substrate;

an RF source coupled to an RF electrode;

a pedestal located in the processing chamber and adapted to support a substrate; and

a UV source configured to delivery UV light to the processing chamber during at least a portion of an etch process performed within the plasma etching apparatus.

2. The plasma etching apparatus of claim 1 further comprising:

a plurality of conductive pins adapted to contact and support the substrate during processing; and

a DC bias source coupled to the plurality of conductive pins.

3. The plasma etching apparatus of claim 2, wherein the plurality of conductive pins pass through the pedestal, and the pedestal is stationary.

4. The plasma etching apparatus of claim 2, comprising a controller having:

an RF pulse generator coupled to the RF source and adapted to produce an RF pulse; and

a DC pulse generator coupled to the DC bias source and adapted to produce a DC bias pulse.

5. The plasma etching apparatus of claim 4, wherein each of the RF pulse generator and the DC pulse generator are synchronized by a master clock.

6. The plasma etching apparatus of claim 4, wherein each of the RF pulse generator and the DC pulse generator may include a delay relative to a master clock.

7. The plasma etching apparatus of claim 4, wherein the DC pulse generator is driven at a frequency of between about 1 MHz and about 60 MHz.

8. The plasma etching apparatus of claim 4, wherein the RF pulse generator is driven at a frequency of between about 2 MHz and about 120 MHz.

9. The plasma etching apparatus of claim 4, wherein the DC pulse generator produces a DC bias pulse having a duty cycle of between 10% and 90%.

10. The plasma etching apparatus of claim 4, wherein the DC bias source produces a bias power of between about 10 W and about 2,000 W.

11. The plasma etching apparatus of claim 4, wherein the DC pulse generator comprises amplitude modulation.

12. A copper plasma etching method, comprising:

providing a substrate within a process chamber;

providing a process gas to the process chamber;

exposing the process gas in the process chamber to RF pulses;

plasma etching the substrate within the process chamber; and

exposing at least one of the process gas and substrate to UV light during at least a portion of the plasma etching.

13. The method of claim 12, further comprising providing DC bias pulses to the substrate through conductive pins in electrically conductive contact with the substrate.

14. The method of claim 13, comprising varying a frequency of the DC bias pulses.

15. The method of claim 13, comprising varying a frequency of the RF pulses and the frequency of the DC bias pulses.

16. The method of claim 13, comprising varying a duty cycle the DC bias pulses.

17. The method of claim 13, comprising modulating amplitude of the DC bias pulses.

18. The method of claim 12, comprising removing copper residue from the substrate.

19. The method of claim 13, wherein the DC bias pulses have a bias power of between about 10 W and about 2,000 W.

20. A copper plasma etching method, comprising:

providing a substrate within a process chamber;

providing a process gas to the process chamber;

exposing the process gas in the process chamber to RF energy to generate a plasma within the process chamber;

plasma etching the substrate within the process chamber; and

exposing at least one of the process gas and substrate to UV light during at least a portion of the plasma etching.