Method of cleaning etching apparatus

• US 20060191555A1
• Filed: 08/15/2005
• Published: 08/31/2006
• Est. Priority Date: 02/28/2005
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: Shimada, Takeshi, Yoshida, Atsushi, Fujimoto, Kotaro
• Granted Patent: US 7,662,235 B2
• Time in Patent Office: Days
• US Class Current: 134/1.1
• CPC Class Codes: B08B 7/0035 by radiant energy, e.g. UV, laser, light beam or the like

Abstract

To provide a cleaning method for an etching apparatus for a metal film that efficiently removes an etching residue deposited in an etching process chamber, assures the reproducibility of the etching performance, and keeps the etching process chamber in a low-dust-emission condition. Each time one workpiece with a metal film is etched (S1), the interior of the vacuum chamber is cleaned by replacing the workpiece with a dummy substrate (S2), performing a first step of plasma processing using oxygen (O₂) and carbon tetrafluoride (CF₄) to remove a carbon-based deposit pile (S3), and performing a second step of plasma processing using boron trichloride (BCl₃) and chlorine (Cl₂) to remove a residue that could not be removed by the first step and an etching residue of the metal film (S4).

Claims

1. A method of cleaning an etching apparatus that conducts etching of a film to be etched made of a stack of any one layer or more than one layers of gold (Au), platinum (Pt), silver (Ag), titanium (Ti), titanium nitride (TiN), titanium oxide (TiO), aluminum (Al) or an aluminum alloy using as an etching gas a mixed gas produced by adding at least one of methane (CH₄), ethane (C₂H₆), acetylene (C₂H₂), dichloromethane (CH₂Cl₂), dibromomethane (CH₂Br₂), chloromethane (CH₃Cl), bromomethane (CH₃Br) and fluoromethane (CH₃F) to at least one of chlorine (Cl₂), boron trichloride (BCl₃) and hydrogen bromide (HBr),

wherein each time etching of the film to be etched is completed, the substrate (wafer) on which the film to be etched is formed is replaced with a dummy substrate, and a plasma is produced, thereby cleaning the interior of a process chamber.

2. The method of cleaning an etching apparatus according to claim 1, wherein the interior of the process chamber is cleaned by successively performing a first step of cleaning using a plasma of a mixed gas of oxygen (O₂) and carbon tetrafluoride (CF₄) or a plasma of a mixed gas of oxygen (O₂) and trifluoromethane (CHF₃) and a second step of cleaning using a plasma of a mixed gas of boron trichloride (BCl₃) and chlorine (Cl₂).

3. The method of cleaning an etching apparatus according to claim 1, wherein the interior of the process chamber is cleaned by successively performing a first step of cleaning using a plasma of a mixed gas of 87.0-95.2% of oxygen (O₂) and 4.8-13.0% of carbon tetrafluoride (CF₄) under a processing pressure of 5-12 Pa for 20-90 seconds and a second step of cleaning using a plasma of a mixed gas of 10.0-30.0% of boron trichloride (BCl₃) and 70.0-90.0% of chlorine (Cl₂) for 20-90 seconds.