Magnetically enhanced high density plasma-chemical vapor deposition plasma source for depositing diamond and diamond-like films

• US 10,227,692 B2
• Filed: 03/09/2018
• Issued: 03/12/2019
• Est. Priority Date: 12/21/2015
• Status: Active Grant

• Current Assignee: Ionquest Corp.
• Original Assignee: IonQuest LLC
• Inventors: Chistyakov, Roman, Abraham, Bassam Hanna
• Primary Examiner(s): McDonald, Rodney G
• Application Number:
  US15/917,046
• Publication Number:
  US 20180195164A1
• Time in Patent Office: 368 Days
• Field of Search: 20419212, 20419232, 20429831, 20429834, 20429837, 20429806, 20429808, 20429816, 20429817, 20429818, 20429819, 427569, 427571
• CPC Class Codes: C23C 14/0057 using reactive gases other than O2, H2O, N2, NH3 or CH4
• CPC Class Codes: C23C 14/0605 Carbon
• CPC Class Codes: C23C 14/14 Metallic material, boron or silicon
• CPC Class Codes: C23C 14/345 using substrate bias
• CPC Class Codes: C23C 14/3485 using pulsed power to the target
• CPC Class Codes: C23C 14/35 by application of a magnetic field, e.g. magnetron sputtering C23C14/3457 takes precedence
• CPC Class Codes: C23C 14/354 Introduction of auxiliary energy into the plasma
• CPC Class Codes: C23C 16/505 using radio frequency discharges
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32825 Working under atmospheric pressure or higher
• CPC Class Codes: H01J 37/3405 Magnetron sputtering
• CPC Class Codes: H01J 37/3417 Arrangements
• CPC Class Codes: H01J 37/3426 Material
• CPC Class Codes: H01J 37/3435 Target holders (includes backing plates and endblocks)
• CPC Class Codes: H01J 37/345 Magnet arrangements in particular for cathodic sputtering apparatus material of magnets or magnets in general H01F1/00, H01F7/00
• CPC Class Codes: H01J 37/3452 Magnet distribution
• CPC Class Codes: H01J 37/3455 Movable magnets
• CPC Class Codes: H01J 37/3464 Operating strategies
• CPC Class Codes: H01J 37/3467 Pulsed operation, e.g. HIPIMS
• CPC Class Codes: H01L 21/2855 by physical means, e.g. sputtering, evaporation H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/76843 : formed in openings in a dielectric
• CPC Class Codes: H01L 21/76871 : Layers specifically deposited to enhance or enable the nucleation of further layers, i.e. seed layers
• CPC Class Codes: H01L 21/76879 : by selective deposition of conductive material in the vias, e.g. selective C.V.D. on semiconductor material, plating plating on semiconductors in general H01L21/288
• CPC Class Codes: H01L 21/76882 : Reflowing or applying of pressure to better fill the contact hole
• CPC Class Codes: H01L 23/5226 : Via connections in a multilevel interconnection structure
• CPC Class Codes: H01L 23/53238 : Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers

Abstract

A magnetically enhanced HDP-CVD plasma source includes a hollow cathode target and an anode. The anode and cathode form a gap. A cathode target magnet assembly forms magnetic field lines that are substantially perpendicular to a cathode target surface. The gap magnet assembly forms a cusp magnetic field in the gap that is coupled with the cathode target magnetic field. The magnetic field lines cross a pole piece electrode positioned in the gap. This pole piece is isolated from ground and can be connected with a voltage power supply. The pole piece can have a negative, positive, or floating electric potential. The plasma source can be configured to generate volume discharge. The gap size prohibits generation of plasma discharge in the gap. By controlling the duration, value and a sign of the electric potential on the pole piece, the plasma ionization can be controlled. The magnetically enhanced HDP-CVD source can also be used for chemically enhanced ionized physical vapor deposition (CE-IPVD). Gas flows through the gap between hollow cathode and anode. The cathode target is inductively grounded, and the substrate is periodically inductively grounded.

Claims

1. A magnetically enhanced high density plasma source comprising:

a hollow cathode target assembly;

an anode positioned on top of the hollow cathode target assembly, thereby forming a gap between the anode and the hollow cathode target assembly;

a cathode magnet assembly;

two rows of magnets facing each other with the same magnetic field direction that generate a cusp magnetic field in the gap and a magnetic field on a surface of the hollow cathode target assembly with the cathode magnet assembly, the cusp magnetic field comprising magnetic field lines that are substantially perpendicular to the hollow cathode target assembly; and

a radio frequency (RF) power supply connected to the hollow cathode target assembly, the RF power supply generating output voltage with a frequency and amplitude that generates an electric field in the gap substantially perpendicular to the cusp magnetic field lines in the gap, the electric field igniting and sustaining RF plasma discharge between the anode and the hollow cathode target assembly, a frequency and power of the RF power supply being selected to increase a degree of ionization of feed gas atoms.

2. The magnetically enhanced high density plasma apparatus, as defined by claim 1, wherein the cathode target magnet assembly rotates with a speed in a range of about 1-500 revolution per minutes.

3. The magnetically enhanced high density plasma apparatus, as defined by claim 1, further comprising

a substrate holder;

and

a substrate bias power supply, the substrate bias power supply being connected to the substrate holder and generating a bias voltage on a substrate in a range of about −

10 V to −

2000 V.

4. The magnetically enhanced high density plasma apparatus, as defined by claim 3, wherein the substrate bias power supply comprises at least one of an RF power supply, alternating current (AC) power supply, very high frequency (VHF) power supply, direct current (DC) power supply, the substrate bias power supply operating in at least one of a continuous mode, pulse mode, the substrate bias power supply providing different frequencies.

5. The magnetically enhanced high density plasma apparatus, as defined by claim 1, wherein the RF power supply comprises at least one of a pulsed RF power supply, high frequency (HF) power supply, pulsed HF power supply, a frequency of the RF power supply being in a range of about 100 kHz-100 MHz.

6. The magnetically enhanced high density plasma apparatus, as defined by claim 1, wherein the hollow cathode target assembly comprises at least one of B, C, Al, Si, P, S, Ga, Ge, As, Se, In, Sn, Sb, Te, I, Tl, Pb, Bi, Sc, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Au, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Be, Mg, Ca, Sr, Ba, O₂, N₂, F, Cl, H₂.

7. The magnetically enhanced high density plasma apparatus, as defined by claim 1, wherein a feed gas comprises at least one of a noble gas, reactive gas.

8. The magnetically enhanced high density plasma apparatus, as defined by claim 1, wherein the magnetically enhanced high density plasma apparatus operates in a sputter etch mode.

9. The magnetically enhanced high density plasma apparatus, as defined by claim 1, wherein the magnetically enhanced high density plasma apparatus operates in a reactive ion etch (ME) mode.

10. The magnetically enhanced high density plasma apparatus, as defined by claim 1, further comprising at least one of permanent magnets, electromagnets, thereby forming the cusp magnetic field.

11. The magnetically enhanced high density plasma apparatus, as defined by claim 1, further comprising an inductor connected between the hollow cathode target assembly and a ground, thereby providing inductive grounding of the hollow cathode target assembly.

12. The magnetically enhanced high density plasma apparatus, as defined by claim 1, wherein the magnetically enhanced high density plasma apparatus operates in a chemical vapor deposition (CVD) mode.

13. A method of generating of magnetically enhanced high density plasma comprising:

providing a hollow cathode target assembly;

forming a gap between the hollow cathode target assembly and an anode;

positioning a hollow cathode target magnet assembly;

generating a cusp magnetic field in the gap such that magnetic field lines are substantially perpendicular to a surface of the hollow cathode target assembly;

providing a radio frequency (RF) power to the cathode target to ignite and sustain volume discharge; and

selecting a frequency and power of the RF power supply to increase a degree of ionization of feed gas atoms.

14. The method of generating of magnetically enhanced high density plasma, as defined by claim 13, wherein the hollow cathode target assembly is inductively grounded.