Etching equipment including a post processing apparatus for removing a resist film, polymer, and impurity layer from an object

• US 6,299,722 B1
• Filed: 06/07/1995
• Issued: 10/09/2001
• Est. Priority Date: 12/16/1992
• Status: Expired due to Term

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Toda, Akihito
• Primary Examiner(s): Niebling, John F.
• Assistant Examiner(s): NGUYEN, HA T
• Application Number:
  US08/478,814
• Time in Patent Office: 2,316 Days
• Field of Search: 156/345, 156/626.1, 216/59, 216/60, 118/715
• US Class Current: 156/345.25
• CPC Class Codes: H01L 21/30604 Chemical etching
• CPC Class Codes: Y10S 438/907 Continuous processing

Abstract

The present invention discloses a method including the main etching step for etching a semiconductor wafer having a resist film serving as an etching mask by plasma of an etching gas, and an post-processing step for processing the object after the main etching so as to remove remaining part of the resist film, a polymer adhered to the surface of the object, and an impurity layer created during the primary etching. In the post-processing step, O₂ gas is made into plasma, by which the remaining part of the resist layer, and the polymer adhered to the surface of the object are removed, and after such a process is substantially finished, a mixture gas including a halogen-containing gas such as CF₄ and O₂ gas is made into plasma, by which the impurity layer is removed.

Claims

1. Etching equipment comprising:

an etching apparatus for main etching an object having a resist film as an etching mask with a plasma produced by an etching gas;

a post-processing apparatus for removing a resist film remaining on the object after the main etching step, a polymer deposited on the surface of the object, and a damage layer formed by the main etching treatment; and

transfer means for transferring the object from the etching apparatus to the post-processing apparatus,

wherein;

the post-processing apparatus includes a processing chamber, first gas supply means for supplying an O₂ gas or a mixture of an O₂ gas and an inert gas into the processing chamber, second gas supply means for supplying a halogen-containing gas or a mixture of a halogen-containing gas and an inert gas into the processing chamber, and switching means for switching supply by the first gas supply means to a gas supply by the second gas supply means;

the object, after the main etching treatment, is treated with a plasma treatment produced by the gas supply by the first gas supply means and consisting essentially of an O₂ gas or a mixture of an O₂ and an inert gas so as to remove a resist film remaining on the object and a polymer deposited on the surface of the object; and

after substantially completing the plasma treatment, the gas supply through the first and second gas supply means is switched by the switching means to perform a plasma treatment with a plasma produced by a gas mixture consisting essentially of a halogen-containing gas and an O₂ gas or a halogen-containing gas, an O₂ gas, and an inert gas so as to remove an impurity layer formed by the main etching.

2. The equipment according to claim 1, wherein said switching means includes an end point detection device for detecting completion of the plasma process by means of plasma produced from the gas including O₂ gas in said post-processing apparatus, and performs switching of gas in accordance with an instruction from said end point detection device.