Tray for transporting wafers and method for fixing wafers onto the tray

• US 8,582,274 B2
• Filed: 02/09/2010
• Issued: 11/12/2013
• Est. Priority Date: 02/18/2009
• Status: Active Grant

• Current Assignee: Ulvac Incorporated
• Original Assignee: Ulvac Incorporated
• Inventors: Kamimura, Ryuichiro, Watanabe, Kazuhiro, Hashimoto, Ryuji
• Primary Examiner(s): Nguyen, Danny
• Application Number:
  US12/991,674
• Publication Number:
  US 20110292561A1
• Time in Patent Office: 1,372 Days
• Field of Search: 361/234, 361/230
• US Class Current: 361/234
• CPC Class Codes: H01L 21/67109 mainly by convection
• CPC Class Codes: H01L 21/6831 using electrostatic chucks

Abstract

A tray for transporting a wafer is herein provided, which can control the temperature of the wafer upon the processing thereof, and which can easily fix the wafer without reducing the effective area on the surface of the wafer and without requiring much time for the adhesion of the wafer thereto and without requiring any post-treatment after the wafer is detached from or attached to the tray. The tray 302 is one which comprises a base body consisting of an insulating material and an electrostatic chuck electrode 306 embedded in the base body, wherein the terminal at a load-dispatching or power supply portion for energizing the electrostatic chuck electrode is a spring-type terminal 305a, the spring-type terminal is so designed that the tip of the same can come in touch with the electrostatic chuck electrode, and further the tray is so designed that a sealing member 305b is provided at the periphery of the load-dispatching portion so that any heat-exchanging medium never passes around the contact portion or area between the tip of the spring-type terminal and the electrostatic chuck electrode and that the tray can thus fixe the wafer S thereto through the electrostatic chucking. Thus, the wafer is fixed to this wafer-transporting tray by the action of the electrostatic chucking.

Claims

1. A method for fixing a wafer characterized in that it comprises the steps of placing a wafer on a tray for transporting the same, which comprises a base body consisting of an insulating material and an electrostatic chuck electrode embedded in the base body, wherein a terminal at a load-dispatching or power supply portion for energizing the electrostatic chuck electrode is a spring-type terminal, the spring-type terminal is so designed that the tip of the same can come in touch with the electrostatic chuck electrode to thus allow the tray to fix the wafer by an electrostatic chucking system upon passing an electric current through the same, and further the tray is so designed that a sealing member is provided at the periphery of the load-dispatching portion so that any heat-exchange medium never passes around a contact portion or area between the tip of the spring-type terminal and the electrostatic chuck electrode;

conveying the tray provided thereon with a wafer to a plasma-processing chamber to thus mount the tray on a tray-supporting stage;

fixing the tray onto the tray-supporting stage by a mechanical chuck or an electrostatic chuck; and

then supplying an electric power to the spring-type terminal to thus fix the wafer to the tray by an electrostatic chucking system.

3. The method for fixing a wafer as set forth in claim 1, wherein a mono-polar electrostatic chuck or a bipolar electrostatic chuck is used as the electrostatic chuck.

4. The method for fixing a wafer as set forth in claim 1, wherein the wafer used is an insulating substrate, the electrostatic chuck used is a mono-polar electrostatic chuck and the generation of plasma is initiated within the plasma-treating chamber upon the supply of an electric current to the spring-type terminal to thus fix the wafer to the tray by the electrostatic chucking system.

2. A method for fixing a wafer characterized in that it comprises the steps of placing a wafer on a tray for transporting the same, which is composed of a base body made of an electrically conductive material, whose surface is covered with an insulating material and an electrostatic chuck electrode embedded in the base body, wherein a terminal at a load-dispatching portion for energizing the electrostatic chuck electrode is a spring-type terminal, the spring-type terminal is so designed that the tip of the same can come in touch with the electrostatic chuck electrode to thus allow the tray to fix the wafer by an electrostatic chucking system upon passing an electric current through the same, and further the tray is so designed that a sealing member is provided at the periphery of the load-dispatching portion so that any heat-exchanging medium never passes around a contact portion or area between the tip of the spring-type terminal and the electrostatic chuck electrode;

conveying the tray provided thereon with a wafer to a plasma-processing chamber to thus mount the tray on a tray-supporting stage;

fixing the tray onto the tray-supporting stage by a mechanical chuck or an electrostatic chuck; and

then supplying an electric power to the spring-type terminal to thus fix the wafer to the tray by an electrostatic chucking system.

5. The method for fixing a wafer as set forth in claim 2, wherein a mono-polar electrostatic chuck or a bipolar electrostatic chuck is used as the electrostatic chuck.

6. The method for fixing a wafer as set forth in claim 2, wherein the wafer used is an insulating substrate, the electrostatic chuck used is a mono-polar electrostatic chuck and the generation of plasma is initiated within the plasma-treating chamber upon the supply of an electric current to the spring-type terminal to thus fix the wafer to the tray by the electrostatic chucking system.

7. A tray for transporting a wafer which comprises a base body consisting of an insulating material and an electrostatic chuck electrode embedded in the base body, wherein a terminal at a load-dispatching or power supply portion for energizing the electrostatic chuck electrode is a spring-type terminal, the spring-type terminal is so designed that the tip of the same contacts the electrostatic chuck electrode to fix the wafer to the tray by an electrostatic chucking system upon passing an electric current through the same, and further the tray is so designed that a sealing member is provided at the periphery of the load-dispatching portion so that any heat-exchanging medium never passes around a contact portion or area between the tip of the spring-type terminal and the electrostatic chuck electrode, and wherein the tray is further provided with a plurality of flow paths for allowing a heat-exchange medium to pass through the same, which are formed through the tray and thus communicate the back face with the surface thereof, and each of the flow paths is so designed that it can supply, to the back face of the wafer, the heat-exchange medium which is introduced into a space formed between the back face of the tray and the surface of a wafer-supporting stage, when the tray is placed on the stage, and wherein the wafer fixed to the tray by the electrostatic chucking system upon passing the electric current through the same is placed in a concave region defined on the surface of the tray by a tray cover disposed at the tray.

8. A tray for transporting a wafer which is composed of an electrically conductive material and an insulating material covering the surface of the former, wherein a terminal at a load-dispatching portion for energizing the electrically conductive material serving as an electrostatic chuck electrode is a spring-type terminal, the spring-type terminal is so designed that the tip of the same contacts the electrically conductive material to fix the wafer to the tray by an electrostatic chucking system upon passing an electric current through the same, and further the tray is so designed that a sealing member is provided at the periphery of the load-dispatching portion so that any heat-exchanging medium never passes around a contact portion or area between the tip of the spring-type terminal and the electrostatic chuck electrode and wherein the tray is further provided with a plurality of flow paths for allowing a heat-exchange medium to pass through the same, which are formed through the tray and thus communicate the back face with the surface thereof, and each of the flow paths is so designed that it can supply, to the back face of the wafer, the heat-exchange medium which is introduced into a space formed between the back face of the tray and the surface of a wafer-supporting stage, when the tray is placed on the stage, and wherein the wafer fixed to the tray by the electrostatic chucking system upon passing the electric current through the same is placed in a concave region defined on the surface of the tray by a tray cover disposed at the tray.

9. A tray for transporting a wafer which comprises a base body consisting of an insulating material and an electrostatic chuck electrode embedded in the base body, wherein a terminal at a load-dispatching or power supply portion for energizing the electrostatic chuck electrode is a spring-type terminal, the spring-type terminal is so designed that the tip of the same contacts the electrostatic chuck electrode to fix the wafer to the tray by an electrostatic chucking system upon passing an electric current through the same, and further the tray is so designed that a sealing member is provided at the periphery of the load-dispatching portion so that any heat-exchanging medium never passes around a contact portion or area between the tip of the spring-type terminal and the electrostatic chuck electrode, and wherein the wafer fixed to the tray by the electrostatic chucking system upon passing the electric current through the same is placed in a concave region defined on the surface of the tray by a tray cover disposed at the tray.

10. A tray for transporting a wafer which is composed of an electrically conductive material and an insulating material covering the surface of the former, wherein a terminal at a load-dispatching portion for energizing the electrically conductive material serving as an electrostatic chuck electrode is a spring-type terminal, the spring-type terminal is so designed that the tip of the same contacts the electrically conductive material to fix the wafer to the tray by an electrostatic chucking system upon passing an electric current through the same, and further the tray is so designed that a sealing member is provided at the periphery of the load-dispatching portion so that any heat-exchanging medium never passes around a contact portion or area between the tip of the spring-type terminal and the electrostatic chuck electrode, and wherein the wafer fixed to the tray by the electrostatic chucking system upon passing the electric current through the same is placed in a concave region defined on the surface of the tray by a tray cover disposed at the tray.