Method for continuous production of sputter-coated glass products

• US 3,925,182 A
• Filed: 07/08/1974
• Issued: 12/09/1975
• Est. Priority Date: 09/25/1973
• Status: Expired due to Term

• Current Assignee: BOC Group PLC The Chertsey Road Windlesham Surrey England GU20 6HJ
• Original Assignee: Chong T. Wan, Donald C. Carmichael, Douglas L. Chambers
• Inventors: Carmichael, Donald C., Chambers, Douglas L., Wan, Chong T.
• Primary Examiner(s): Mack, John H.
• Assistant Examiner(s): Weisstuch, Aaron
• Application Number:
  US05/486,492
• Time in Patent Office: 519 Days
• Field of Search: 204/192,298 118/49.1,49.5
• US Class Current: 204/192.27
• CPC Class Codes: C03C 17/00 Surface treatment of glass, not in the form of fibres or filaments, by coating optical coatings of optical elements G02B1/10
• CPC Class Codes: C23C 14/568 Transferring the substrates through a series of coating stations C23C14/562 takes precedence

Abstract

A method and apparatus for the continuous production of sputtercoated glass products; such as glass sheets, or other substrates, involving supporting one or more substrates to be coated on a rigid support-platen, passing the platens and substrates horizontally through a series of successive chambers aligned with one another, including an entrance chamber, a coating chamber and a discharge chamber, sealing compartments at the opposite ends of the coating chamber, at the entry end of the entrance chamber and at the exit end of the discharge chamber for sealing said chambers from one another and from the atmosphere, conveyor means in said chambers for carrying the platens and substrates therethrough, and means responsive to movement of the platens through said chambers for automatically and in timed sequence initiating and controlling the complete cycle of operations of the apparatus, including the travel of the platens through the successive chambers, the opening and closing of the sealing compartments and the sputter-coating of one or more continuous films of a selected material or materials on the substrates as they pass through the coating chamber.

Claims

1. A METHOD FOR THE PRODUCTION OF SPUTTER-COATED GLASS SHEETS, WHICH COMPRISES:

A. FREELY SUPPORTING A GLASS SHEET TO BE COATED IN A HORIZONTAL POSITION ON THE UPPER SUBSTANTIALLY CONTINUOUS SURFACE OF A SUPPORT PLATEN, B. FREELY SUPPORTING SAID PLATEN AND GLASS SHEET HORIZONTALLY UPON A CONVEYOR MEANS, C. CONVEYING THE PLATEN AND SHEET HORIZONTALLY INTO A COATING CHAMBER, D. MAINTAINING A PREDETERMINED PRESSURE IN SAID COATING CHAMBER, E. SPUTTER-COATING A CONTINUOUS FILM OF A SELECTED COATING MATERIAL ON THE UPPER SURFACE OF SAID SHEET WHEN SUPPORTED IN THE COATING CHAMBER, AND F. REMOVING THE PLATEN AND COATED SHEET FROM SAID CHAMBER.

2. The method of claim 1 in which an inert gas is continuously introduced into the central region of said coating chamber and continuously withdrawn laterally therefrom adjacent the opposite ends thereof to remove gas that is leaked into said chamber and thereby maintain a constant pressure therein.

3. The method of claim 1, in which the sputter-coating means comprises a plurality of cathodes connected to individual power sources, and in which the power level to each individual cathode is independently controlled by movement of the platen.

4. A method for the production of sputter-coated glass sheets, (and the like), which comprises:

a. freely supporting a glass sheet to be coated in a horizontal position on the upper substantially continuous surface of a support platen, b. freely supporting said platen and glass sheet horizontally upon a conveyor means, c. conveying the platen and sheet horizontally into and through a series of at least three successive chambers having communication with one another and in which the central chamber is a coating chamber, d. sealing the coating chamber from the adjacent chambers when the platen and sheet are received therein, e. maintaining a predetermined pressure in the coating chamber, f. continuously circulating an inert gas through the coating chamber to maintain an inert gas atmosphere therein, g. sputter-coating a continuous film of a selected coating material on the upper surface of said sheet as it is conveyed through the coating chamber, and h. establishing communication between the coating chamber and the adjacent chambers in response to movement of the platen and sheet prior to and during delivery of the platen and sheet into the coating chamber and the subsequent discharge thereof from said coating chamber while maintaining the pressure in said coating chamber.

5. The method of claim 4 wherein, in response to movement of the platen, a pressure is established and maintained in the chambers adjacent the coating chamber equal to the pressure in the coating chamber prior to and during the transfer of the platen into said coating chamber and its discharge therefrom, and in which the pressure in the chambers adjacent the coating chamber is subsequently released while the pressure in said coating chamber is maintained.

6. The method of claim 4, in which a desired pressure is created in the chambers adjacent the coating chamber, and then introducing an inert gas into the adjacent chambers to equalize the pressures therein with the pressure in the coating chamber prior to and during transfer of the platen and sheet into the coating chamber and its discharge therefrom by by-passing inert gas from the coating chamber into the adjacent chambers.

7. The method of claim 4, including the steps of heating the glass sheet and then cleaning said sheet by means of a glow discharge cleaning electrode prior to sputter-coating, and in which the power level to the cleaning electrode is controlled by movement of the support platen to guard against over-heating of said electrode.

8. A method for the production of sputter-coated glass sheets, which comprises:

a. freely supporting a glass sheet to be coated in a horizontal position on the upper substantially continuous surface of a support platen, b. freely supporting said platen and glass sheet horizontally upon a conveyor means, c. conveying the platen and sheet horizontallY into and through a series of at least three chambers having communication with one another and including an entrance chamber, a coating chamber and a discharge chamber, d. sealing the coating chamber from the entrance and discharge chambers when the platen and sheet are received therein, e. maintaining a predetermined pressure in the coating chamber, f. sputter-coating a continuous film of a selected coating material on the upper surface of the sheet as it is conveyed through said coating chamber, and g. effecting in timed sequence in response to movement of the platen the sealing of the entrance chamber and discharge chamber to the ambient atmosphere and the creation of a pressure in said chambers equal to that in the coating chamber prior to establishing communication between said chambers and conveying the platen and sheet from the entrance chamber into the coating chamber and from the coating chamber into the discharge chamber.

9. The method of claim 8, including the steps of introducing an inert gas into the coating chamber, pumping down the entrance chamber and discharge chamber to a desired vacuum, backfilling the entrance and discharge chambers with an inert gas until the pressures therein are substantially equal to the pressure in the coating chamber, and then bringing the pressures in said entrance, coating and discharge chambers into equilibrium by by-passing inert gas from the coating chamber into the entrance and discharge chambers.

10. A method for the production of sputter-coated glass sheets, which comprises:

a. freely supporting a glass sheet to be coated in a horizontal position on the upper substantially continuous surface of a support platen, b. freely supporting said platen and glass sheet horizontally upon a conveyor means, c. conveying the platen and sheet horizontally into and through a series of at least three chambers having communication with one another and including an entrance chamber, a coating chamber and discharge chamber, d. sealing the coating chamber from the entrance chamber and discharge chamber when the platen and sheet are received therein, e. maintaining a predetermined pressure in the coating chamber, f. continuously circulating an inert gas through the coating chamber to maintain an inert gas atmosphere therein, g. sputter-coating a continuous film of a selected coating material on the upper surface of the sheet as it is conveyed through said coating chamber, h. establishing communication between the coating chamber and the entrance and discharge chambers in response to movement of said platen prior to and during transfer of the platen and sheet from the entrance chamber into the coating chamber and from the coating chamber into the discharge chamber, i. sealing the entrance chamber and discharge chamber from the ambient atmosphere in response to movement of said platen prior to and during such transfer to maintain the pressure in the coating chamber, and j. in timed sequence and in response to movement of the platen re-establishing communication between the entrance and discharge chambers and the ambient atmosphere after the platen and sheet have been conveyed from the entrance chamber into the coating chamber and from the coating chamber into the discharge chamber.

11. The method of claim 10, wherein the pressure in the entrance chamber and discharge chamber is equalized with the pressure in the coating chamber prior to and during transfer of the platen and sheet from the entrance chamber into the coating chamber and from the coating chamber into the discharge chamber, and wherein the pressure in the entrance chamber and discharge chamber is released after the platen is received in the coating chamber and subsequently discharged therefrom respectively in timed response to movement of said platen.

12. The method of claim 10, in which an initial pressure is first established in the entrance and discharge chambers, and in which thE said chambers are then backfilled with an inert gas to equalize the pressure therein with the pressure in the coating chamber piror to and during the conveying of the platen and sheet from the entrance chamber into the coating chamber and from the coating chamber into the discharge chamber.

13. A method for the production of sputter-coated glass sheets, which comprises:

a. supporting a sheet to be coated in a horizontal position on the upper surface of a support platen, b. passing the platen and sheet horizontally through a series of at least three chambers having communication with one another and including an entrance chamber, a coating chamber and a discharge chamber, c. sealing the coating chamber from the entrance chamber and discharge chamber when the platen and sheet are received therein. d. maintaining the coating chamber at a constant pressure in the range of 2 to 6 X 10 2 torr, e. circulating an inert gas through the coating chamber to maintain an inert gas atmosphere therein, f. sputter-coating a continuous film of a selected coating material on the upper surface of the sheet as it is carried through said coating chamber, g. establishing communication between the coating chamber and the entrance and discharge chambers during transfer of the platen and sheet from the entrance chamber into the coating chamber, and h. sealing the entrance chamber and discharge chamber from the atmosphere during such transfer to maintain the pressure in the coating chamber, i. in which the sputter-coating means comprises a plurality of cathodes and in which the power level to each indicidual cathode is independently controlled by movement of the platen.

14. A method for production of sputter-coating glass sheets, which comprises:

a. freely supporting a glass sheet to be coated in a horizontal position on the upper substantially continuous surface of a support platen, b. freely supporting said platen and glass sheet horizontally upon a conveyor means, c. conveying the platen and sheet horizontally into, through and out of a series of at least three chambers having communication with one another and including an entrance chamber, a coating chamber and a discharge chamber, d. maintaining a predetermined pressure in the coating chamber, and e. sputter-coating a continuous film of a selected coating material on the upper surface of the sheet as it is conveyed through said coating chamber, and in which, in timed sequence, and in response to movement of said platen through successive chambers, the following process steps are initiated and controlled;

i. sealing the coating chamber from the entrance chamber and discharge chamber during the sputter-coating of the glass sheet, ii. sealing the entrance chamber and discharge chamber to the ambient atmosphere when the platen and sheet are received therein, iii. establishing and maintaining a pressure in the entrance chamber and discharge chamber equal to the pressure in the coating chamber prior to and during transfer of the platen and sheet from the entrance chamber into the coating chamber and from the coating chamber into the discharge chamber, iv. establishing communication between the coating chamber and entrance and discharge chambers during conveying of the platen and sheet from the entrance chamber into the coating chamber and from the coating chamber into the discharge chamber, v. resealing the coating chamber from the entrance and discharge chambers respectively after the platen and sheet have been received in the coating chamber and subsequently moved from said coating chamber into the discharge chamber, and vi. opening the entrance chamber and discharge chamber to the ambient atmosphere after the coating chamber has been resealed.