Abstract: An electroless copper plating bath for depositing a copper or copper alloy layer on a surface of a substrate, including copper ions; a reducing agent; a complexing agent for copper ions; wherein the bath further includes at least one compound according to formula (1): in which Z1 and Z2 are independently selected from the group consisting of hydrogen; carboxylic acid; carboxylate; sulfonic acid; sulfonate; carboxamide; nitrile; nitro; trialkylammonium; 2-carboxyvinyl; 2-vinylcarboxylate; 2-(trialkylammonium)vinyl; hydroxamic acid; and oxime; provided at least one of Z1 and Z2 is not hydrogen; and in which R1, R2, R3 and R4 are: i. R1, R2, R3 and R4 are hydrogen; or ii. R1 with R2 form together an aromatic ring, R3 and R4 are hydrogen; or iii. R3 with R4 form together an aromatic ring, R1 and R2 are hydrogen; or iv. both R1 with R2 and R3 with R4 form together an aromatic ring, respectively.

Abstract: An electroless copper plating bath for depositing a copper or copper alloy layer on a surface of a substrate, including copper ions; a reducing agent; a complexing agent for copper ions; wherein the bath further includes at least one compound according to formula (1): in which Z1 and Z2 are independently selected from the group consisting of hydrogen; carboxylic acid; carboxylate; sulfonic acid; sulfonate; carboxamide; nitrile; nitro; trialkylammonium; 2-carboxyvinyl; 2-vinylcarboxylate; 2-(trialkylammonium)vinyl; hydroxamic acid; and oxime; provided at least one of Z1 and Z2 is not hydrogen; and in which R1, R2, R3 and R4 are: i. R1, R2, R3 and R4 are hydrogen; or ii. R1 with R2 form together an aromatic ring, R3 and R4 are hydrogen; or iii. R3 with R4 form together an aromatic ring, R1 and R2 are hydrogen; or iv. both R1 with R2 and R3 with R4 form together an aromatic ring, respectively.

Abstract: The present invention relates to a method for reducing the optical reflectivity of a copper and copper alloy circuitry wherein a thin palladium or palladium alloy layer is deposited by immersion-type plating onto said copper or copper alloy. Thereby, a dull greyish or greyish black or black layer is obtained and the optical reflectivity of said copper or copper alloy circuitry is reduced. The method according to the present invention is particularly suitable in the manufacture of image display devices, touch screen devices and related electronic components.

Abstract: The present invention relates to a method for reducing the optical reflectivity of a copper and copper alloy circuitry wherein a thin palladium or palladium alloy layer is deposited by immersion-type plating onto said copper or copper alloy. Thereby, a dull greyish or greyish black or black layer is obtained and the optical reflectivity of said copper or copper alloy circuitry is reduced. The method according to the present invention is particularly suitable in the manufacture of image display devices, touch screen devices and related electronic components.