Shielding for arc suppression in rotating magnetron sputtering systems

• US 5,725,746 A
• Filed: 03/21/1995
• Issued: 03/10/1998
• Est. Priority Date: 08/10/1990
• Status: Expired due to Term

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Viratec Thin Films, Inc. (Apogee Enterprises Incorporated)
• Inventors: Bjornard, Erik J., Dickey, Eric R.
• Primary Examiner(s): NGUYEN, NAM X
• Application Number:
  US08/408,022
• Time in Patent Office: 1,085 Days
• Field of Search: 204/298.11, 204/298.12, 204/298.16, 204/298.19, 204/298.21, 204/298.23, 204/298.28
• US Class Current: 204/298.21
• CPC Class Codes: C23C 14/3407 Cathode assembly for sputtering apparatus, e.g. Target
• CPC Class Codes: C23C 14/3414 Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
• CPC Class Codes: H01J 2237/0206 Extinguishing, preventing or controlling unwanted discharges
• CPC Class Codes: H01J 37/3405 Magnetron sputtering

Abstract

A cathode body for a rotating cylindrical magnetron wherein the magnetron provides a sputtering zone extending along the length of the cathode body and circumferentially along a relatively narrow region thereof. The cathode body includes an elongated tubular member having a target material at the outer surface thereof. A collar of electrically-conductive material is located at at least one end of the tubular member, and extends along the tubular member from that one end into the erosion zone. A sleeve of electrically-conductive material may extend circumferentially around the collar.

Claims

1. A rotating cylindrical magnetron sputtering apparatus for sputtering a thin film of a selected coating material on a substrate using a gas discharge, comprising:

an evacuable coating chamber;

a cathode including an elongated cylindrical tubular member having a layer of target material at the surface thereof and having a racetrack-shaped sputtering zone extending along the length of said tubular member with a turn around region at each end thereof, said turn around regions including a collar material having a sputtering rate less than that of said target material and a melting point higher than that of said target material, wherein a contiguous surface of said tubular member, extending over a majority of said sputtering zone, is substantially free of said collar material;

means for rotabably supporting said tubular member in said coating chamber; and

means for transporting said substrate past said sputtering zone to receive the thin film, said thin film being substantially free of said collar material at least in an area between the edges of said substrate.

2. The apparatus of claim 1 wherein sputtered collar material forms another compound having electrical insulating properties less than that of said coating material.

3. A rotating cylindrical magnetron sputtering a first thin film of a selected material on a designated area of a substrate, comprising:

an elongated cylindrical tubular member having a layer of target material on a surface thereof and including a magnetic means for defining a sputtering zone extending along the length and circumferentially along a relatively narrow region of said tubular member;

and a collar of electrically conductive material different from said target material on at least one end of said tubular member, said collar extending circumferentially about said tubular member and along said tubular member inward from an edge of said sputtering zone, and said collar material having a sputtering rate less than that of said target material and a melting point greater than that of said target material, and sputtered collar material forming another compound having electrical insulating properties less than that of said coating material so as to reduce the insulating property of a second film deposited outside of said designated substrate area, wherein a contiguous surface of said tubular member, extending over a majority of said sputtering zone, is substantially free of said collar material, whereby said first thin film is substantially free of said collar material at least in an area between the edges of said substrate.