Microelectronics and Computer Technology Corporation

Charles W Lin

Ian Y Yee

Tom J Hirsch

Chung J Lee

Ernest R Nolan

Randy L German

Nalin Kumar

Heinrich G Muller

David M Sigmond

Kimcuc T Tran

A method of selectively fabricating metallization on a dielectric substrate is disclosed. A seed layer is sputtered on a polymer dielectric, a patterned photoresist mask is disposed over the seed layer, exposed portions of the seed layer are etched, the photoresist is stripped, and copper is deposited without a mask by electroless plating on the unetched seed layer to form well-adhering high density copper lines without exposing the photoresist to the electroless bath.

Selective patterning of metallization on a dielectric substrate

The invention provides an apparatus and methods of using the apparatus to transfer conductive patterns onto substrates under conditions of heat and pressure. The apparatus comprises a master mold with a printing surface on which is produced a permanent mirror image of the conductive pattern to be created. This pattern is then coated with a loosely adherent film of conductive metal, such as copper, which is transferred onto a substrate to be printed.

Method for producing conductive patterns

A method for selectively electroplating a metallic coating, such as solder, onto a plurality of small and closely spaced electrical contacts. The method includes sealingly enclosing the contacts in an electroplating cell having an anode, a cathode and a chamber, forming an electrical connection between the cathode and the contacts and electroplating the contacts.

Methods and apparatus for electroplating electrical contacts

A method and apparatus for selectively electroplating a metallic coating, such as solder, onto a plurality of small and closely spaced electrical contacts. The method includes sealingly enclosing the contacts in an electroplating cell having an anode, a cathode and a chamber, forming an electrical connection between the cathode and the contacts and electroplating the contacts.

Apparatus for electroplating electrical contacts

A dielectric substrate is coated with a protective layer and a catalyst film is formed in a laser irradiated predetermined pattern on the protective layer so that during electroless deposition a metal is plated on the catalyst film in the predetermined pattern whether or not the dielectric has unwanted catalytic sites. The protective layer is not removed by the electroless plating bath or prior etch steps but can subsequently be stripped by a separate etch without removing the plated metal or the dielectric from the substrate.

Protective layer for preventing electroless deposition on a dielectric

A method for electrolessly plating an overcoat metal on a metal conductor disposed on a dielectric surface of a substrate. The method includes removing carbonized film from the dielectric surface by applying a plasma discharge, acid treating the metal conductor by dipping the substrate in a first acid solution in order to clean the surface of the metal conductor, activating the metal conductor to allow electroless plating thereon by dipping the substrate in a metal activator solution, deactivating the dielectric surface to prevent electroless plating thereon without deactivating the metal conductor by dipping the substrate in a second acid solution, and plating an overcoat metal on the metal conductor by dipping the substrate in an electroless plating solution so that the overcoat metal plates on and coats the metal conductor without plating on the dielectric surface.

Selective electroless plating process for metal conductors

Method for making a multilayer electrical interconnect with stacked pillars between layers using a minimal number of conventional process steps. The method includes sputtering a chromium/copper/titanium trilayer on a dielectric base, depositing a patterned mask on the trilayer, etching the exposed trilayer, removing the mask, depositing a layer of polyimide over the unetched copper, forming a via in the polyimide above the copper, electrolessly plating nickel into the via, and polishing the interconnect to form a planar top surface.

Multilayer electrical interconnect fabrication with few process steps

A method for detecting the completion of electrolessly depositing metal into a via. The method includes providing a non-autocatalytic detection mask with an opening over a via containing an autocatalytic material, electrolessly depositing a conductive metal into the via which fails to plate to the mask, and continuing the deposition until metal in the via contacts the mask, at which time the electrochemical potential of the mask changes and the metal plates to and covers the entire mask. The completion of the electroless via fill can be detected by changes in both the appearance and electrochemical potential of the mask.

Detecting completion of electroless via fill

A method for patterning electroless plated metal on a polymer substrate. In a first embodiment a substrate is first coated with a polymer suitable for complexing a seed metal which can initiate electroless plating. The polymer is then mixed with a seed metal such as palladium, selectively irradiated to form the desired conductor pattern, and then etched so that the desired pattern remains. The substrate is subsequently placed in an electroless plating bath to form a metal pattern. In a second embodiment, before applying the seed metal a substrate immersed in a polymer solution suitable for complexing a seed metal can be selectively irradiated to selectively deposit polymer on the substrate, followed by applying a seed metal to form a polymer-seed metal mixture and an electroless plating bath. In addition, an alkaline chemical may be added to an acidic polymer to prevent the polymer from etching metal on the substrate.

Method for patterning electroless plated metal on a polymer substrate

A method is described for patterning electroless plated metal on a polymer substrate. A substrate is first coated with a polymer suitable for complexing noble metal compounds. The substrate is then complexed with a noble metal compound, such as containing palladium, selectively irradiated to form the desired conductor pattern, and then etched so that the desired pattern remains. The substrate is subsequently placed in an electroless plating bath to form a metal pattern. Alternatively, before applying the noble metal compound, a substrate immersed in a polymer solution suitable for complexing a noble metal compound can be selectively irradiated to selectively deposit polymer on the substrate, followed by applying a noble metal compound and an electroless plating bath.

Method of patterning electroless plated metal on a polymer substrate

A process and solution for selectively etching copper. The etching is effected by a nonaqueous solution of dimethyl sulfoxide and a halocarbon compound.

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San Antonio, TX, United States of America

Charles W Lin