Shielding for arc suppression in rotating magnetron sputtering systems
AssigneeViratec Thin Films, Inc.
InventorsEric R. Dickey, Erik J. Bjornard
Life of this patent
Estimating the term…
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.
Claims20
A rotating cylindrical magnetron sputtering apparatus for D.C. reactive sputtering a film of silicon dioxide on a substrate using a gas discharge, comprising:
- an evacuable coating chamber;
- a cathode including an elongated cylindrical tubular member having a layer of silicon at the surface thereof and having a magnet array defining a sputtering zone extending along the length of said tubular member and circumferentially along a relatively narrow region thereof, said sputtering zone defining an erosion zone about said tubular member and along the length thereof;
- means for rotatably supporting said tubular member in said coating chamber;
- means for transporting the substrate past the sputtering zone;
- and
- means for suppressing arcing due to a dielectric breakdown of an insulating layer deposited on at least one of a dark-space shield, support structure or end portion of the cathode, including a collar formed of a material selected from a group consisting of scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, zirconium, molybdenum, hafnium, tantalum, tungsten, rhodium, platinum, and iridium, said collar disposed around at least one end of said tubular member and said collar having a first end outside said erosion zone and a second end extending into the erosion zone a distance sufficient that said collar material may be sputtered, said collar material having a sputtering rate less than that of silicon and a melting point greater than silicon, said sputtered collar material forming a compound having electrical insulating properties less than that of silicon dioxide to reduce the voltage drop across said insulating layer and thereby suppress arcing in said coating chamber, wherein a contiguous surface of said tubular member, extending over a majority of said erosion zone, is substantially free of said collar material, whereby said silicon dioxide film is substantially free of said collar material at least in an area between the edges of said substrate.
A cathode body for a rotating cylindrical magnetron for D.C. reactive sputter deposition of a film including a compound of a target material, wherein the magnetron includes a magnet array for defining a sputtering zone extending along the length of the cathode body, comprising:
- an elongated tubular member having said target material at the outer surface thereof;
- and
- on at least one end of said tubular member a collar extending along said tubular member from a portion thereof outside said sputtering zone and into said sputtering zone, said collar formed of a material having a sputtering rate less than that of said target material and sputtered collar material forming another compound having electrical insulating properties less than that of said compound of said target material so as to suppress arcing, 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 film is substantially free of said sputtered collar material at least in an area between the edges of said substrate.
A rotating cylindrical magnetron for D.C. reactive sputtering a first thin film of a selected compound of a target material on a designated area of a substrate, comprising:
- an elongated cylindrical tubular member having a layer of said 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 from a portion thereof outside said sputtering zone and into 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 compound of said target 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.
Dependencies are inferred from the claim text.