PLASMA OXIDATION PROCESSING METHOD

• US 20090263919A1
• Filed: 08/27/2007
• Published: 10/22/2009
• Est. Priority Date: 08/28/2006
• Status: Active Grant

• Current Assignee: Nagoya University, Tokyo Electron Limited
• Original Assignee: Nagoya University, Tokyo Electron Limited
• Inventors: Shiozawa, Toshihiko, Kabe, Yoshiro, Kitagawa, Junichi, Hori, Masaru
• Granted Patent: US 7,989,364 B2
• Time in Patent Office: Days
• US Class Current: 438/5
• CPC Class Codes: C23C 8/10 Oxidising
• CPC Class Codes: C23C 8/36 using ionised gases, e.g. ionitriding
• CPC Class Codes: H01L 21/02238 silicon in uncombined form, i.e. pure silicon
• CPC Class Codes: H01L 21/02252 formation by plasma treatment, e.g. plasma oxidation of the substrate after treatment of an insulating film by plasma H01L21/3105 and subgroups
• CPC Class Codes: H01L 21/31662 of silicon in uncombined form
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps

Abstract

A plasma oxidation process is performed to form a silicon oxide film on the surface of a target object by use of plasma with an O(¹D₂) radical density of 1×10¹² [cm⁻³] or more generated from a process gas containing oxygen inside a process chamber of a plasma processing apparatus. During the plasma oxidation process, the O(¹D₂) radical density in the plasma is measured by a VUV monochromator 63, and a correction is made to the plasma process conditions.

Claims

1. A plasma oxidation processing method comprising:

generating plasma with an O(¹D₂) radical density of 1×

10¹² [cm<sup>−

3</sup>] or more from a process gas containing oxygen inside a process chamber of a plasma processing apparatus; and

performing an oxidation process on a surface of a target object by the plasma,

wherein the plasma is a microwave excitation plasma generated from the process gas by microwaves supplied from a planar antenna including a plurality of slots into the process chamber,

the plasma oxidation process is arranged to use a pressure of 1.33 to 334 Pa inside the process chamber, and

the process gas has an oxygen ratio of 0.2 to 1%.

3. The plasma oxidation processing method according to claim 1, wherein the oxidation process is performed on silicon of the surface of the target object to form a silicon oxide film.

4. The plasma oxidation processing method according to claim 3, wherein the plasma is used to oxidize a silicon surface exposed in a recessed portion formed on the target object, so as to form the silicon oxide film.

5. The plasma oxidation processing method according to claim 4, wherein the silicon oxide film is formed while a curved surface shape is formed on a silicon corner portion at an upper end of a sidewall of the recessed portion.

6. The plasma oxidation processing method according to claim 3, wherein the silicon is mono-crystalline silicon or poly-crystalline silicon.

9. The plasma oxidation processing method according to claim 1, wherein the process gas contains hydrogen at a ratio of 1% or less.

10. The plasma oxidation processing method according to claim 1, wherein the plasma is excited by use of a microwave power of 1 W/cm² or more.

2. (canceled)

7-8. -8. (canceled)

11. A plasma oxidation processing method comprising:

generating microwave excitation plasma from a process gas containing oxygen inside a process chamber of a plasma processing apparatus;

measuring an O(¹D₂) radical density in the plasma; and

performing an oxidation process on a target object by plasma with an O(¹D₂) radical density of 1×

10¹² [cm<sup>−

3</sup>] or more,

wherein the method further comprises making a correction to plasma generating conditions with reference to a measurement result of the O(¹D₂) radical density.

12. (canceled)

13. The plasma oxidation processing method according to claim 12, wherein the plasma generating conditions comprise one or more of a process pressure, an oxygen ratio in the process gas, and a microwave power for exciting the plasma.

14-19. -19. (canceled)

20. A plasma processing apparatus comprising:

a process chamber configured to be vacuum-exhausted and to perform a plasma process on a target object;

a planar antenna including a plurality of slots and configured to supply microwaves into the process chamber;

a measuring mechanism configured to measure an O(¹D₂) radical density in the plasma; and

a control section preset to control plasma generating conditions with reference to a measurement result of the O(¹D₂) radical density, so as to set the O(¹D₂) radical density to be 1×

10¹² [cm<sup>−

3</sup>] or more.