Zinc oxide film treatment method and method of manufacturing photovoltaic device utilizing the same

• US 7,282,132 B2
• Filed: 03/22/2004
• Issued: 10/16/2007
• Est. Priority Date: 03/25/2003
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Miyamoto, Yusuke, Iwata, Masumitsu, Sonoda, Yuichi, Toyama, Noboru, Kondo, Takaharu, Hayashi, Ryo, Yamada, Satoru, Nishimoto, Tomonori
• Primary Examiner(s): King; Hoy
• Assistant Examiner(s): Leader; William T.
• Application Number:
  US10/805,323
• Publication Number:
  US 20040191949A1
• Time in Patent Office: 1,303 Days
• Field of Search: 205/224, 205/199
• US Class Current: 205/199
• CPC Class Codes: C25D 9/04 with inorganic materials
• CPC Class Codes: H01L 31/056 the light-reflecting means being of the back surface reflector [BSR] type
• CPC Class Codes: H01L 31/1864 Annealing
• CPC Class Codes: H01L 31/1884 Manufacture of transparent electrodes, e.g. TCO, ITO
• CPC Class Codes: Y02E 10/52 PV systems with concentrators
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A film of zinc oxide electrochemically deposited from an aqueous solution is subjected to heat treatment at a temperature equal to or higher than 150° C. and equal to or lower than 400° C. in a nitrogen or inert gas atmosphere that contains oxygen, thereby obtaining a zinc oxide film that is low in electric resistance without impairing the light transmittance of the zinc oxide film.

Claims

1. A zinc oxide film treatment method for heating a film of zinc oxide electrochemically deposited on an electroconductive substrate from an aqueous solution,

wherein heat treatment is carried out at a treatment temperature of 150°

C. or higher and 400°

C. or lower in a N₂ or inert gas atmosphere that contains oxygen, and

wherein an oxygen partial pressure ratio to N₂ or inert gas is 1% or higher and lower than 10%.

2. A zinc oxide film treatment method according to claim 1, wherein a treatment pressure is set to 5 kPa or higher and lower than 50 kPa.

3. A zinc oxide film treatment method according to claim 2, wherein the inert gas is one of helium, argon, and a mixture gas of helium and argon.

4. A zinc oxide film treatment method according to claim 2, wherein the electroconductive substrate is a substrate in continuous form and is subjected to heat treatment while wound into a roll.

5. A zinc oxide film treatment method according to claim 2, wherein the temperature of the treatment subject is raised to a treatment temperature at a rate of 2.0°

C./min or less.

6. A method of manufacturing a photovoltaic device, comprising a step of forming, on a zinc oxide film heated by a zinc oxide film treatment method of claim 2, semiconductor layers at a temperature lower than the treatment temperature.