Plasma Treatment Method and Plasma Etching Method

• US 20080085604A1
• Filed: 07/06/2005
• Published: 04/10/2008
• Est. Priority Date: 07/07/2004
• Status: Abandoned Application

• Current Assignee: Showa Denko KK, Tohoku University National Universities Corporation
• Original Assignee: Showa Denko KK, Tohoku University National Universities Corporation
• Inventors: Hoshino, Yasuyuki, Samukawa, Seiji
• Application Number:
  US11/631,597
• Publication Number:
  US 20080085604A1
• Time in Patent Office: Days
• US Class Current: 438/712
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching
• CPC Class Codes: H01L 21/31116 by dry-etching
• CPC Class Codes: H01L 21/32137 of silicon-containing layers

Abstract

The present invention develops a process for plasma treatment using a gas having no greenhouse effect in order to realize global environmental preservation and sophistication of plasma process performance and provides a process for plasma etching with high accuracy which process can depress damage to devices. The process for plasma treatment according to the present invention comprises the steps of feeding a treatment gas containing fluorine gas (F₂) into a plasma generating chamber, alternately repeating application of high frequency electric field and stop of the application thereof to generate plasma, and carrying out substrate treatment by irradiating the plasma to a substrate. Furthermore, the substrate treatment may be carried out by individually or alternately extracting negative ions or positive ions from the plasma, or selectively extracting only negative ions, neutralizing them, to generate a neutral beam and irradiating the neutral beam to the substrate.

Claims

1. A process for plasma treatment which process comprises the steps of:

feeding a treatment gas containing fluorine gas (F₂) into a plasma generating chamber,

alternately repeating application of a high frequency electric field and stop of the application thereof to generate plasma, and

carrying out substrate treatment by irradiating the plasma to a substrate.

4. The process for plasma treatment according to claim 1, wherein the treatment gas is 100% by volume of fluorine gas (F₂).

5. The process for plasma treatment according to claim 1, wherein the treatment gas is a mixed gas of fluorine gas (F₂) and chlorine gas Cl₂.

6. The process for plasma treatment according to claim 1, wherein the fluorine gas (F₂) is fluorine gas (F₂) generated by thermally decomposing a solid metal fluoride.

7. The process for plasma treatment according to claim 1, wherein in generating the plasma, the gas pressure of a plasma generating chamber is from 0.1 to 100 Pa.

8. The process for plasma treatment according to claim 1, wherein in generating the plasma, the stop time of application of high frequency electric field is from 20 to 100 μ

sec.

9. A process for fluorination treatment which process is characterized by utilizing the process for plasma treatment as claimed in claim 1.

10. A process for plasma etching a substrate which process is characterized by utilizing the process for plasma treatment as claimed in claim 1.

11. A process for plasma etching silicon or a silicon compound which process is characterized by utilizing the process for plasma etching as claimed in claim 10.

12. The process for plasma etching according to claim 11 wherein the silicon compound comprises silicon oxide, silicon nitride or a silicate.

13. A semiconductor device produced by the process as claimed in claim 1.

14. A micro machine (MEMS:

Micro Electric Mechanical System) device produced by the process as claimed in claim 1.

2. A process for plasma treatment which process comprises the steps of:

feeding a treatment gas containing fluorine gas (F₂) into a plasma generating chamber,

alternately repeating application of a high frequency electric field and stop of the application thereof to generate plasma,

individually or alternately extracting negative ions or positive ions from the plasma and neutralizing them to generate a neutral beam, and

carrying out substrate treatment by irradiating the neutral beam to a substrate.

3. A process for plasma treatment which process comprises the steps of:

feeding a treatment gas containing fluorine gas (F₂) into a plasma generating chamber,

alternately repeating application of a high frequency electric field and stop of the application thereof to generate plasma,

selectively extracting only negative ions from the plasma and neutralizing them to generate a neutral beam, and

carrying out substrate treatment by irradiating the neutral beam to a substrate.