Enhanced charged particle beam processes for carbon removal

Patent metadata

Field	Value
Publication number	US-10347463-B2
Application number	US-201615374617-A
Country	US
Kind code	B2
Filing date	Dec 9, 2016
Priority date	Dec 9, 2016
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

Method and system for enhanced charged particle beam processes for carbon removal. With the method and system for enhancing carbon removal, associated method and system for decreasing levels of carbon impurity in depositions, also using a precursor gas in charged particle beam processes (and particularly focused ion beam methodologies), are provided. In a preferred embodiment, the precursor gas comprises methyl nitroacetate. In alternative embodiments, the precursor gas is methyl acetate, ethyl acetate, ethyl nitroacetate, propyl acetate, propyl nitroacetate, nitro ethyl acetate, methyl methoxyacetate, or methoxy acetylchloride.

First claim

We claim as follows:

1. A method of chemically-enhanced charged particle beam milling of a work piece area, the method comprising:
providing an etch-assisting gas to a surface of the work piece area targeted for milling, wherein at least a portion of the surface of the targeted work piece area consists essentially of carbonaceous material;
directing a focused ion beam toward the portion of the surface that consists essentially of carbonaceous material, thereby removing carbon from the targeted area at a removal rate greater than a removal rate when no etch-assisting gas is used;
in which:
the etch-assisting gas comprises a chemical selected from a group consisting of methyl nitroacetate, methyl acetate, ethyl acetate, ethyl nitroacetate, propyl acetate, propyl nitroacetate, nitro ethyl acetate, methyl methoxyacetate, and methoxy acetylchloride; and
the carbonaceous material is selected from the group consisting of diamond, vitreous carbon, polyimide material, and organic resin comprising other carbon-rich polymer material.

2. The method of claim 1 in which the focused ion beam originates from a plasma focused ion beam source.

3. The method of claim 1 in which ions of the focused ion beam are selected from the group consisting of: Xe + , Ar + , Kr + , O + , O 2 + , N + , N 2 + , NO + , and NO 2 + .

4. The method of claim 1 in which the focused ion beam operates during carbon removal at a very low or low acceleration voltage ranging from about 2 keV to about 14 keV.

5. The method of claim 1 in which the etch-assisting gas chemical is methyl nitroacetate.

6. The method of claim 1 in which the carbon-rich polymer material is selected from the group consisting of polycarbonate, polyester, polyethylene, polypropylene, polystyrene, and polyurethane.

7. A method of charged particle beam cleaning of a surface contaminated with hydrocarbon material, the method comprising:
providing a carbon-removal precursor gas to a surface area targeted for cleaning;
directing a charged particle beam toward the surface area targeted for cleaning, thereby removing hydrocarbon contaminant material from the surface at a removal rate greater than a removal rate when no carbon-removal precursor gas is used;
in which:
the carbon-removal precursor gas comprises a chemical selected from a group consisting of methyl nitroacetate, methyl acetate, ethyl acetate, ethyl nitroacetate, propyl acetate, propyl nitroacetate, nitro ethyl acetate, methyl methoxyacetate, and methoxy acetylchloride.

8. The method of claim 7 in which the charged particle beam is a focused ion beam.

9. The method of claim 8 in which the focused ion beam originates from a plasma focused ion beam source.

10. The method of claim 9 in which ions originating from the plasma focused ion beam source are selected from the group consisting of: Xe+, Ar+, Kr+, O+, O2+, N+, N2+, NO+, and NO2+.

11. The method of claim 9 in which the plasma focused ion beam operates during surface cleaning at an acceleration voltage ranging from about 2 keV to about 30 keV.

12. The method of claim 9 in which the plasma focused ion beam operates during surface cleaning at an acceleration voltage ranging from about 2 keV to about 5 keV.

13. The method of claim 12 in which ions originating from the plasma focused ion beam source are Xe+ ions.

Assignees

• Fei Co

Inventors

• Rue Chad
• Christian Joe
• Mani Kenny
• Franco Noel Thomas

Classifications

• H10P70/27

  during, before or after processing of conductive materials, e.g. polysilicon or amorphous silicon layers · CPC title

• H10P70/20

  Cleaning during device manufacture · CPC title

• H10P70/12 Primary

  by dry cleaning only (H10P70/52 takes precedence) · CPC title

• H10P50/287

  by chemical means · CPC title

• H10P50/285

  of materials not containing Si, e.g. PZT or Al2O3 · CPC title