Thin film deposition apparatus

Claim 2

Apparatus for depositing a thin film on a length of substrate which comprises: supply means carrying a supply of substrate to be coated, take-up means for accumulating coated substrate length, a pressure vessel having means therein for establishing a sputtering plasma condition within the vessel, anode means mounted in the vessel, cathode means comprising a plurality of targets secured on the interior of the vessel, each target having a surface formed of the material to be sputtered, the surface facing the exterior surface of the anode means but spaced therefrom, the said targets being circumferentially spaced with the said planar surfaces thereof defining at least part of a cylindrical surface that is coaxial with but larger in diameter than the anode means whereby to form a plurality of consecutive arcuate gaps within which the sputtering plasma is adapted to be established, a high voltage source connected in a circuit which includes the anode means and the cathode means, structure disposed within the vessel and arranged to guide the substrate length from the supply to the take-up means in a configuration establishing a tortuous path including at least a portion of a circular turn around the anode means, for substantially lengthwise movement of said substrate length and the said path being such as to expose only one surface of said substrate to the sputtering plasma condition while said substrate is in said tortuous path.

Claim 3

The apparatus as claimed in claim 1 in which structure is provided for controlling at least the surface temperature of the substrate length while it is moving along the path.

Claim 4

The apparatus as claimed in claim 2 in which means are provided to cover the second surface of said substrate length while it is moving along said path.

Claim 5

The apparatus as claimed in claim 1 in which the tortuous path comprises a series of convolutions and said anode means comprises a drum having at least a substantial portion of each convolution engaging the exterior surface of said drum.

Claim 6

The apparatus as claimed in claim 4 in which means are provided to rotate the drum and carry the convolutions circumferentially of the drum and to move the same axially along the length of the drum.

Claim 7

The apparatus as claimed in claim 5 in which said means for moving the convolutions axially along the length of the drum comprise convolution shifting means.

Claim 8

The apparatus as claimed in claim 6 in which said convolutions form a helix along the length of said drum.

Claim 9

The apparatus as claimed in claim 4 in which said targets are of arcuate configuration arranged generally coaxial and telescopically of said drum and spaced outwardly thereof to form an annular plasma vapor gap between each of the said targets and the outer surface of said convolution.

Claim 10

The apparatus as claimed in claim 8 in which said targets comprise a plurality of arcuate members at least some of which are circumferentially spaced apart having means for individually adjusting the respective members.

Claim 11

The apparatus as claimed in claim 8 in which means are provided for establishing a magnetic field across said gap to sweep secondary electrons out of said path.

Claim 12

The apparatus as claimed in claim 10 in which said last means comprise coaxial cooperating magnetic members on the inside of said drum and outside of said targets and the field is radial.

Claim 13

The apparatus as claimed in claim 1 in which means are provided in said vessel to decrease surface charge on said substrate comprising a source of photons in said vessel.

Claim 14

The apparatus as claimed in claim 5 in which said drum surface is provided with heat absorbing means.

Claim 15

The apparatus as claimed in claim 13 in which said last means is a black coating.

Claim 16

The apparatus as claimed in claim 1 in which the tortuous path comprises at least one convolution and said structure comprises a drum having at least a substantial portion of the convolution engaging the exterior surface of the drum.

Claim 17

Apparatus for depositing a thin film on a length of substrate which comprises: a supply of substrate to be coated, means for accumulating coated substrate length, a pressure vessel having means therein for establishing a plasma vapor deposition condition within the vessel, structure disposed within the vessel and arranged to guide the substrate length from the supply to the accumulating means in a configuration establishing a tortuous path for substantially lengthwise movement of said substrate length and the said path being such as repeatedly to expose one surface of said substrate length to the depositing condition while said substrate is in said tortuous path, said tortuous path comprising a series of convolutions and said structure comprising a drum having at least a substantial portion of each convolution engaging the exterior surface of said drum, means for rotating said drum and carrying the convolutions circumferentially of said drum to move same axially along the length of said drum, said means for moving said convolutions axially comprising convolution shifting means, said convolutions forming a helix along the length of said drum, said convolutions comprising a series of parallel turns arranged along the length of the drum and the convolution shifting means comprising structure for forming a cross-connecting bight between successive turns at the bottom ends thereof.

Claim 18

Apparatus for depositing a thin film on a length of substrate which comprises: a supply of substrate to be coated, means for accumulating coated substrate length, a pressure vessel having means therein for establishing a plasma vapor deposition condition within the vessel, structure disposed within the vessel and arranged to guide the substrate length from the supply to the accumulating means in a configuration establishing a tortuous path for substantially lengthwise movement of said substrate length and the said path being such as repeatedly to expose one surface of said substrate length to the depositing condition while said substrate is in said tortuous path, said tortuous path comprising a series of convolutions and said structure comprising a drum having at least a substantial portion of each convolution engaging the exterior surface of said drum, means for rotating said drum and carrying the convolutions circumferentially of said drum to move same axially along the length of said drum, said means for moving said convolutions axially comprising convolution shifting means, said convolutions forming a helix along the length of said drum, said convolutions comprising a series of parallel turns arranged along the length of the drum and the convolution shifting means comprising structure for forming a cross-connecting bight between successive turns at the bottom ends thereof.

Claim 19

The apparatus as claimed in claim 16 in which the bights hang loosely to enable the flexing thereof.

Claim 20

The apparatus as claimed in claim 16 in which said shifting means include a pair of rollers engaging the surface of said drum and having the substrate engaging said exterior surface of the drum tightly pressed against said surface but having the substrate subtended between the rollers opposite said surface forming said bights loosely.

Claim 21

The apparatus as claimed in claim 18 in which one of said rollers is mounted for applying continuous pressure against said drum and means is provided for biasing the other to overdrive to maintain tension on the portion of said substrate engaging said drum surface.

Claim 22

Apparatus for depositing a thin film on a length of substrate which comprises: a supply of substrate to be coated, means for accumulating coated substrate length, a pressure vessel having means therein for establishing a plasma vapor deposition condition within the vessel, structure disposed within the vessel and arranged to guide the substrate length from the supply to the accumulating means in a configuration establishing a tortuous path for substantially lengthwise movement of said substrate length and the said path being such as repeatedly to expose one surface of said substrate length to the depositing condition while said substrate length is in said tortuous path, said tortuous path comprising a series of convolutions and said structure comprising a drum having at least a substantial portion of each convolution engaging the exterior surface thereof, means for rotating said drum and carrying said convolutions circumferentially of the drum to move the same axially along the length of said drum, said means for moving the convolutions axially along the length of the drum comprising convolution shifting means, said convolutions forming a helix along the length of said drum and comprising a series of parallel turns arranged along said length and said convolution shifting means comprising structure for forming a cross-connecting loosely hanging bight between successive turns at the bottom ends thereof, said structure additionally including target means of arcuate configuration generally coaxial and telescopic of said drum and spaced outwardly thereof to form an annular plasma vapor gap between the said target means and the outer surfaces of said convolutions and substantially coextensive in area with the portion of the drum adapted to be occupied by said turns and open at least opposite the locations of said bights.

Claim 23

Apparatus for depositing a thin film on a length of substrate which comprises: a supply of substrate to be coated, means for accumulating coated substrate length, a pressure vessel having means therein for establishing a plasma vapor deposition condition within the vessel, structure disposed within the vessel and arranged to guide the substrate length from the supply to the accumulating means in a configuration establishing a tortuous path for substantially lengthwise movement of said substrate length and the said path being such as repeatedly to expose one surface of said substrate length to the depositing condition while said substrate length is in said tortuous path, said tortuous path comprising a series of convolutions and said structure comprising a drum having at least a substantial portion of each convolution engaging the exterior surface thereof, means for rotating said drum and carrying said convolutions circumferentially of the drum to move the same axially along the length of said drum, said means for moving the convolutions axially along the length of the drum comprising convolution shifting means, said convolutions forming a helix along the length of said drum and comprising a series of parallel turns arranged along said length and said convolution shifting means comprising structure for forming a cross-connecting loosely hanging bight between successive turns at the bottom ends thereof, said structure additionally including target means of arcuate configuration generally coaxial and telescopic of said drum and spaced outwardly thereof to form an annular plasma vapor gap between the said target means and the outer surfaces of said convolutions and substantially coextensive in area with the portion of the drum adapted to be occupied by said turns and open at least opposite the locations of said bights.

Claim 24

The apparatus as claimed in claim 20 in which said target means comprise a plurality of arcuate members at least some of which are circumferentially spaced apart and having means for individually adjusting the respective members.

Claim 25

Apparatus for depositing a thin film on a length of flexible substrate which comprises: A. a pressure vessel including an enclosing side wall and enclosing end walls and means for establishing a sputtering plasma condition within the vessel and including i. anode means in the form of a rotary drum mounted on one end wall for rotation on a shaft defining an axis passing through both end walls, ii. cathode means comprising a plurality of targets on the interior of the vessel secured to the side wall and each target having a planar surface of the material to be sputtered which faces the exterior surface of the drum and is spaced therefrom, the targets being circumferentially spaced around the periphery of the drum and said planar surfaces generally defining at least part of a cylindrical surface that is coaxial with but larger in diameter than the drum whereby to form a plurality of consecutive arcuate gaps within which the sputtering plasma is adapted to be established, and iii. a high voltage source connected in a circuit which includes the anode means and the cathode means, the cathode means being at a substantially high negative voltage with respect to the anode means, B. a supply of flexible substrate to be coated, arranged in a reel form and the substrate adapted to be stripped off from the reel and pass through said gaps, C. take-up means for accumulating coated substrate in reel form, D. means disposed within the vessel and cooperating with the drum to cause movement of the substrate while passing within the vessel from the supply to the take-up means in a tortuous path, said tortuous path including at least a portion of a circular turn around the drum with the substrate tightly engaged against the surface of the drum, E. the said path being such as repeatedly to expose only the outer surface of the substrate to the sputtering plasma condition of respective gaps by guiding said substrate through said gaps while so engaged against the drum.

Claim 26

Apparatus for depositing a thin film on a length of flexible substrate which comprises: A. a pressure vessel including an enclosing side wall and enclosing end walls and means for establishing a sputtering plasma condition within the vessel and including i. anode means in the form of a rotary drum mounted on one end wall for rotation on a shaft defining an axis passing through both end walls, ii. cathode means comprising a plurality of targets on the interior of the vessel secured to the side wall and each target having a planar surface of the material to be sputtered which faces the exterior surface of the drum and is spaced therefrom, the targets being circumferentially spaced around the periphery of the drum and said planar surfaces generally defining at least part of a cylindrical surface that is coaxial with but larger in diameter than the drum whereby to form a plurality of consecutive arcuate gaps within which the sputtering plasma is adapted to be established, and iii. a high voltage source connected in a circuit which includes the anode means and the cathode means, the cathode means being at a substantially high negative voltage with respect to the anode means, B. a supply of flexible substrate to be coated, arranged in a reel form and the substrate adapted to be stripped off from the reel and pass through said gaps, C. take-up means for accumulating coated substrate in reel form, D. means disposed within the vessel and cooperating with the drum to cause movement of the substrate while passing within the vessel from the supply to the take-up means in a tortuous path, said tortuous path including at least a portion of a circular turn around the drum with the substrate tightly engaged against the surface of the drum, E. the said path being such as repeatedly to expose only the outer surface of the substrate to the sputtering plasma condition of respective gaps by guiding said substrate through said gaps while so engaged against the drum.

Claim 27

The apparatus as claimed in claim 22 in which the tortuous path includes more than a circular turn around the drum whereby the outer surface of the substrate will be subjected to the sputtering plasma condition of the respective gaps more than one time each.

Claim 28

The apparatus as claimed in claim 22 in which the enclosing side wall is of metal and the targets are insulated from the latter enclosing wall.

Claim 29

The apparatus as claimed in claim 22 in which the anode is at ground potential.

Claim 30

The apparatus as claimed in claim 22 in which the anode is negative with respect to ground.

Claim 31

The apparatus as claimed in claim 22 in which the cathode planar surfaces are arcuate.

Claim 32

The apparatus as claimed in claim 22 in which the supply and take-up means are both on the interior of the vessel.

Claim 33

The apparatus as claimed in claim 22 in which means are provided to control the temperature of the substrate by controlling the temperature of the surface of the drum.

Claim 34

The apparatus as claimed in claim 22 in which means are provided in the drum adjacent the surface thereof for controlling the temperature of the surface of the drum.

Claim 35

The apparatus as claimed in claim 22 in which first heat exchange liquid conduit means are provided in the drum adjacent the surface thereof for controlling the temperature of the surface of the drum, said drum having second heat exchange liquid conduit means connected with said first heat exchange liquid conduit means and extending through said drum shaft to the exterior of said vessel and adapted to be coupled to an external source of heat exchange liquid, the arrangement being such as to provide for circulation of said liquid through said conduits while the coating is being carried out.

Claim 36

The apparatus as claimed in claim 22 in which there are means for individually adjusting the gap of each target by moving the target radially relative to the drum.

Claim 37

The apparatus as claimed in claim 22 in which means are provided for cooling the targets comprising coolant conduits in the targets and means for extending passageways for carrying liquid coolants to and from the targets through the side enclosing wall and said passageways being coupled to a source of such coolant exterior of the vessel.

Claim 38

The apparatus as claimed in claim 23 in which there are means to transfer the substrate in axial direction along the surface of the drum while said substrate is being laid onto such surface at one axial end of the turns and being stripped off at the other axial end of the turns.

Claim 39

The apparatus as claimed in claim 34 in which the transfer means comprise turn shifting means.

Claim 40

The apparatus as claimed in claim 34 in which the transfer means comprise structure for forming a cross-connecting bight at the bottom of the drum between respective adjacent turns.