PULSED DC PLASMA ETCHING PROCESS AND APPARATUS

• US 20140273487A1
• Filed: 03/07/2014
• 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, Liu, Jingjing, Deshmukh, Subhash
• Application Number:
  US14/200,779
• Publication Number:
  US 20140273487A1
• Time in Patent Office: Days
• US Class Current: 438/714
• CPC Class Codes: H01J 37/32091 the radio frequency energy being capacitively coupled to the plasma
• CPC Class Codes: H01J 37/32146 Amplitude modulation, includes pulsing
• CPC Class Codes: H01J 37/32706 Polarising the substrate
• CPC Class Codes: H01J 37/32715 Workpiece holder
• CPC Class Codes: H01J 37/32724 Temperature
• CPC Class Codes: H01L 21/31116 by dry-etching
• CPC Class Codes: H01L 21/32136 using plasmas
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 21/68742 characterised by a lifting arrangement, e.g. lift pins
• CPC Class Codes: H01L 21/6875 characterised by a plurality of individual support members, e.g. support posts or protrusions

Abstract

In one aspect, a plasma etching apparatus is disclosed. The plasma etching apparatus includes 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, a plurality of conductive pins adapted to contact and support the substrate during processing, and a DC bias source electrically coupled to the plurality of conductive pins. Etching methods are provided, as are numerous other aspects.

Claims

1. A plasma etching apparatus, 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;

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.

2. The plasma etching apparatus of claim 1, wherein the plurality of conductive pins pass through the pedestal, and the pedestal is stationary.

3. The plasma etching apparatus of claim 1, wherein the number of pins comprises more than three.

4. The plasma etching apparatus of claim 1, wherein the pedestal comprises a heater.

5. The plasma etching apparatus of claim 1, wherein the pedestal comprises a ceramic having holes receiving the plurality of conductive pins.

6. The plasma etching apparatus of claim 1, 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.

7. The plasma etching apparatus of claim 6, wherein each of the RF pulse generator and the DC pulse generator are synchronized by a master clock.

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

9. The plasma etching apparatus of claim 6, wherein the DC pulse generator is driven at a frequency of between about 1 MHz and about 60 MHz.

10. The plasma etching apparatus of claim 6, wherein the RF pulse generator is driven at a frequency of between about 2 MHz and about 120 MHz.

11. The plasma etching apparatus of claim 6, wherein the DC pulse generator produces a DC bias pulse having a duty cycle of between 10% and 90%.

12. The plasma etching apparatus of claim 6, wherein the DC bias source produces a bias power of between about 10W and about 2,000W.

13. The plasma etching apparatus of claim 6, wherein the DC pulse generator comprises amplitude modulation.

14. A plasma etching method, comprising:

providing the substrate within a process chamber;

providing a process gas to the process chamber;

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

providing DC bias pulses to the substrate through conductive pins in electrically conductive contact with the substrate.

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

16. The method of claim 14, comprising varying a frequency of the RF pulses and the frequency of the DC bias pulses.

17. The method of claim 14, comprising varying a duty cycle the DC bias pulses.

18. The method of claim 14, comprising modulating amplitude of the DC bias pulses.

19. The method of claim 14, comprising removing copper residue from the substrate.

20. The method of claim 14, wherein the DC bias pulses have a bias power of between about 10W and about 2,000W.