Electroless copper plating on ceramic material

• US 3,296,012 A
• Filed: 04/30/1965
• Issued: 01/03/1967
• Est. Priority Date: 04/30/1965
• Status: Expired due to Term

• Current Assignee: Stewart G. Stalnecker Jr
• Original Assignee: Stewart G. Stalnecker Jr
• Inventors: Stalnecker, Stewart G. Jr.
• Application Number:
  US04/452,333
• Time in Patent Office: 613 Days
• US Class Current: 427/305
• CPC Class Codes: C23C 18/1893 with use of organic or inorganic compounds other than metals, first
• CPC Class Codes: C23C 18/40 using reducing agents
• CPC Class Codes: H05K 1/0306 Inorganic insulating substrates, e.g. ceramic, glass
• CPC Class Codes: H05K 3/181 by electroless plating adhesives therefor H05K3/387
• CPC Class Codes: H05K 3/381 by special treatment of the substrate

Claims

1. IN A METHOD OF CHEMICALLY DEPOSITING COPPER ON A SURFACE OF AN ALUMINA SUBSTRATE COMPRISING THE STEPS OF CLEANING SAID SUBSTRATE, SENSITIZING IT, RINSING IT WITH WATER AND IMMERSING IT IN A PLATING BATH, THE IMPROVEMENT COMPRISING THE STEPS OF MAKING THE SURFACE OF SAID ALUMINA SUBSTRATE SUBMICROSCOPICALLY POROUS BY LEACHING AFTER SAID CLEANING STEP IN A BATH COMPRISING ABOUT 85% AQUEOUS SOLUTION OF ORTHO-PHOSPHORIC ACID, SENSITIZING THE LEACHED SURFACE BY SUCCESSIVELY IMMERSING SAID SUBSTRATE IN AN AQUEOUS SOLUTION OF STANNOUS CHLORIDE AND AN AQUEOUS SOLUTIO OF PALLADIUM CHLORIDE FOR ABOUT 3 MINUTES EACH, AND THEN IMMERSING SAID SUBSTRATE IN A PLATING BATH CONTAINING A SALT OF COPPER TO WHICH BATH TETRASODIUM SALT OF ETHYLENEDIAMINETETRAACETIC ACID HAS BEEN ADDED IN THE AMOUNT OF AT LEAST 0.5% BY VOLUME.