Method for producing transparent conductive films

• US 5,180,476 A
• Filed: 02/26/1991
• Issued: 01/19/1993
• Est. Priority Date: 02/27/1990
• Status: Expired due to Term

• Current Assignee: Nihon Shinku Gijutsu Kabushiki Kaisha
• Original Assignee: Nihon Shinku Gijutsu Kabushiki Kaisha
• Inventors: Komatsu, Takashi, Nakamura, Kyuzo, Higuchi, Yasushi, Ota, Yoshifumi, Murata, Yuzo, Ishibashi, Satoru
• Primary Examiner(s): Weisstuch, Aaron
• Application Number:
  US07/660,840
• Time in Patent Office: 693 Days
• Field of Search: 204/192.29, 204/298.08, 204/298.16-298.22, 204/298.25
• US Class Current: 204/192.29
• CPC Class Codes: C23C 14/086 of zinc, germanium, cadmium, indium, tin, thallium or bismuth
• CPC Class Codes: C23C 14/35 by application of a magnetic field, e.g. magnetron sputtering C23C14/3457 takes precedence
• CPC Class Codes: H01L 31/1884 Manufacture of transparent electrodes, e.g. TCO, ITO
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

A method of producing by sputtering an In-O, Sn-O, Zn-O, Cd-Sn-O or Cd-In-O based transparent conductive film according to the present invention uses the addition of a donor element, if needed. The sputtering is carried out by maintaining an intensity of a magnetic field on a surface of a target at 600 Oe or greater as well as by charging the target with a DC electric field superimposed by an RF electric field. An apparatus for producing an In-O, Sn-O, Zn-O, Cd-Sn-O or Cd-In-O base transparent conductive film uses the addition of a donor element, if needed. The apparatus has a vacuum chamber adapted to support therein a substrate and a target in an opposed relationship for forming by sputtering the transparent conductive film on the substrate by plasma discharge generated therebetween. The apparatus has a device for forming a magnetic field having a predetermined intensity of 600 Oe or greater on a surface of the target, a DC power supply for charging the target with a DC electric field, and an RF power supply for charging the target with an RF electric field superimposed on the DC electric field.

Claims

1. A method of producing an In-O, Sn-O, Zn-O, Cd-Sn-O or Cd-In-O based transparent conductive film with an optional additional of a donor element, said method comprising the steps of:

maintaining an intensity of a magnetic field on a surface of a target at a level of at least 600 Oe; and

sputtering the target so as to form the transparent conductive film on a substrate by charging the target, simultaneously with said maintaining of the magnetic filed intensity, with a DC electric field superimposed with an RF electric field so as to lower the sputtering voltage to 250 volts or less.

2. A method as set forth in claim 1, wherein the target comprises at least one material selected from the group consisting of In, Sn, Zn, Cd-Sn and Cd-In based metals, and In, Sn, Zn, Cd-Sn and Cd-In sintered oxides.

3. A method as set forth in claim 2, wherein the material for the target has a donor element added therein, the donor element comprising at least one material selected from the group consisting of Sn, Sb, In, Al, and Si.