PLASMA PROCESSING APPARATUS AND PLASMA PROCESSING METHOD

• US 20110226734A1
• Filed: 08/12/2010
• Published: 09/22/2011
• Est. Priority Date: 03/16/2010
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: TANAKA, MOTOHIRO, SUMIYA, MASAHIRO
• Granted Patent: US 8,557,709 B2
• Time in Patent Office: Days
• US Class Current: 216/41
• CPC Class Codes: H01J 37/32192 Microwave generated discharge H01J37/32357, H01J37/32366, H01J37/32394, H01J37/32403 take precedence
• CPC Class Codes: H01J 37/3266 Magnetic control means
• CPC Class Codes: H01L 21/02002 Preparing wafers
• CPC Class Codes: H01L 21/0206 during, before or after processing of insulating layers
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02334 in-situ cleaning after layer formation, e.g. removing process residues
• CPC Class Codes: H01L 21/28123 Lithography-related aspects, e.g. sub-lithography lengths; Isolation-related aspects, e.g. to solve problems arising at the crossing with the side of the device isolation; Planarisation aspects
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching
• CPC Class Codes: H01L 21/31116 by dry-etching
• CPC Class Codes: H01L 21/32136 using plasmas
• CPC Class Codes: H01L 21/32137 of silicon-containing layers
• CPC Class Codes: H01L 21/67259 Position monitoring, e.g. misposition detection or presence detection

Abstract

In a plasma processing apparatus comprising a processing chamber arranged in a vacuum chamber, a sample stage arranged under the processing chamber and having its top surface on which a wafer to be processed is mounted, a vacuum decompression unit for evacuating the interior of the processing chamber to reduce the pressure therein, and introduction holes arranged above said sample stage to admit process gas into the processing chamber, the wafer having its top surface mounted with a film structure and the film structure being etched by using plasma formed by using the process gas, the film structure is constituted by having a resist film or a mask film, a poly-silicon film and an insulation film laminated in this order from top to bottom on a substrate and before the wafer is mounted on the sample stage and the poly-silicon film underlying the mask film is etched, plasma is formed inside the processing chamber to cover the surface of members inside the processing chamber with a coating film containing a component of Si.

Claims

1. A plasma processing apparatus comprising:

a processing chamber arranged in a vacuum chamber;

a sample stage arranged under the processing chamber and having its top surface on which a wafer to be processed is mounted;

a vacuum decompression unit for evacuating the interior of said processing chamber to reduce the pressure therein; and

introduction holes arranged above said sample stage to admit process gas into said processing chamber, said wafer having its top surface mounted with a film structure and said film structure being etched by using plasma formed by using said process gas, wherein

said film structure is constituted by having a resist film or a mask film, a poly-silicon film and an insulation film laminated in this order from top to bottom on a substrate and before said wafer is mounted on said sample stage and the poly-silicon film underlying said mask film is etched, plasma is formed inside said processing chamber to cover the surface of members inside said processing chamber with a coating film containing a component of Si.

2. A plasma processing apparatus according to claim 1, wherein in the step of covering said coating film, a gas containing a component of at least one of Si or Si and O or Si and C is supplied to the interior of said processing chamber.

3. A plasma processing apparatus according to claim 1, wherein after, following the step of covering said coating films, an aftertreatment process for forming plasma inside said processing chamber is carried out to process the surface of the coating film, said wafer is located inside said processing chamber and then an etching process is executed.

4. A plasma processing apparatus according to claim 3, wherein said film structure has a metal film made of a metal material and interposed between said poly-silicon film and said insulation film and a cleaning process for forming plasma adapted to eliminate said metal material from said coating film is carried out.

5. A plasma processing method in which a wafer to be processed is mounted on the top surface of a sample stage arranged under a processing chamber disposed inside a decompressed vacuum chamber and plasma is formed by admitting process gas to said processing chamber through introduction holes arranged above said sample stage to etch a film structure mounted on the top surface of said wafer, said film structure being constituted by having a resist film or a mask film, a poly-silicon film and an insulation film laminated in this order from top to bottom on a substrate, wherein

before said wafer is mounted on said sample stage and said poly-silicon film underlying said mask film is etched, plasma is formed inside said processing chamber to cover the surface of members inside said processing chamber with a coating film containing a component of Si.

6. A plasma processing method according to claim 5, wherein in the step of covering said coating film, a gas containing a component of at least one of Si or Si and O or Si and C is supplied to the interior of said processing chamber.

7. A plasma processing method according to claim 5, wherein after, following the step of covering said coating films, an aftertreatment process for forming plasma inside said processing chamber is carried out to process the surface of the coating film, said wafer is located inside said processing chamber and then an etching process is executed.

8. A plasma processing method according to claim 7, wherein said film structure has a metal film made of a metal material and interposed between said poly-silicon film and said insulation film and a cleaning process for forming plasma adapted to eliminate said metal material from said coating film is carried out.