1. A method of metallizing a photovoltaic solar cell to deposit a layer of metal thereon, said photovoltaic solar cell having a front side and a backside, wherein said back side comprises a layer of a metal selected from the group consisting of aluminum and aluminum alloys and said front side comprising a pattern comprising metal thereon, the method comprising the steps of:
a) contacting the photovoltaic solar cell with a light induced plating composition comprising:
i) a source of soluble silver ions; and
ii) an agent that solubilizes aluminum metal ions dissolved from the layer of metal on the back side; and thereafter
b) illuminating the photovoltaic solar cell with radiant energy from a light source,
wherein metal ions from the light induced plating solution are plated onto the metallic pattern on the frontside of the solar cell, and wherein the solar cell is not electrically connected to an external power source during the plating, and wherein ions of the metal layer on the back side are dissolved into the light induced plating composition.
2. The method according to claim 1, wherein the light induced plating composition comprises a complexing agent for the silver ions.
3. The method according to claim 1, wherein the source of soluble silver ions is selected from the group consisting of silver oxide, silver nitrate, silver methanesulfonate, silver acetate, silver citrate, silver sulfate and combinations of one or more of the foregoing.
4. The method according to claim 3, wherein the source of soluble silver ions is silver acetate.
5. The method according to claim 3, wherein the source of soluble silver ions is silver methanesulfonate.
6. The method according to claim 3, wherein the source of soluble silver ions is silver sulfate.
7. The method according to claim 1, wherein the concentration of soluble silver ions is between about 1 and about 35 gramsliter.
8. The method according to claim 1, wherein the solubilizing agent is selected from the group consisting of glyoxylic acid, glycolic acid, lactic acid, any alpha- or ortho-hydroxycarboxylic acids, aliphatic dicarboxylic acids, hydroxy-polycarboxylic acids, or any combinations of the foregoing.
9. The method according to cairn claim 8, wherein the solubilizing agent comprises tartaric acid or salts thereof.
10. The method according to claim 8, wherein the solubilizing agent comprises citric acid or salts thereof.
11. The method according to claim 1, wherein the concentration of the solubilizing agent is between about 1 to 150 gramsliter, but is most preferably from 10 to 30 gramsliter.
12. The method according to claim 2, wherein the complexing agent is selected from the group consisting of cyanide, succinimide or substituted succinimide, hydantoin or substituted hydantoin, uracil, thiosulfate, amines and combinations of one or more of the foregoing.
13. The method according to claim 12, wherein the complexing agent is hydantoin or substituted hydantoin.
14. The method according to claim 2, wherein the concentration of the complexing agent is between about 20 to about 150 gramsliter.
15. The method according to claim 1, wherein the pattern comprising metal on the front side of the solar cell comprises current collection lines and busbars printed thereon.
16. The method according to claim 15, wherein the pattern comprising metal comprises printed silver paste.
17. The method according to claim 1, wherein the light source is a selected from the group consisting of halogen lamps, incandescent lamps, fluorescent lamps, light emitting diodes, or mercury lamps.
18. The method according to claim 1, wherein the step of contacting the photovoltaic cell with the light induced plating composition comprises immersing the photovoltaic cell in the light induced plating composition.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of producing a surface-treated steel sheet comprising:
dipping a steel sheet for 0.1 to 10 seconds into a treatment liquid that contains at least fluoride ions and has a pH of 2 to 5; and
electrically treating by flowing a direct current between the steel sheet and an electrode in a treatment liquid to form a layer that contains a metal oxide on a surface of the steel sheet.
2. The method of producing a surface-treated steel sheet according to claim 1, wherein
dipping includes continuously feeding the steel sheet into a dip treatment bath that is filled with a dip treatment liquid thereby to dip the steel sheet into the dip treatment liquid, and
electrically treating includes, after dipping the steel sheet into the dip treatment liquid, continuously feeding the steel sheet into an electrolytic treatment bath that is filled with a metal ion-containing electrolytic treatment liquid and at least one electrode and electrically treating by flowing the direct current between the steel sheet and the electrode in the electrolytic treatment liquid.
3. The method of producing a surface-treated steel sheet according to claim 2, wherein the dip treatment liquid contains a part of constituents of those contained in the electrolytic treatment liquid.
4. The method of producing a surface-treated steel sheet according to claim 2, wherein aqueous solutions that contain the same constituents are used as the dip treatment liquid and the electrolytic treatment liquid.
5. The method of producing a surface-treated steel sheet according to claim 2, wherein aqueous solutions that contain the same constituents at the same content ratio are used as the dip treatment liquid and the electrolytic treatment liquid.
6. The method of producing a surface-treated steel sheet according claim 2, wherein the electrolytic treatment liquid contains ions of at least one kind of metal selected from Zr, Al and Ti.
7. The method of producing a surface-treated steel sheet according to claim 1, wherein the steel sheet is a cold-rolled steel sheet from which iron is exposed at least one surface thereof.
8. The method of producing a surface-treated steel sheet according to claim 1, wherein a molar concentration of metal in the layer formed on the surface of the steel sheet is 0.3 mmolm2 or more.
9. The method of producing a surface-treated steel sheet according to claim 1, wherein the layer that contains the metal oxide is formed on the surface of the steel sheet without pickling the steel sheet with acid.