In various embodiments, a method of forming an electrical contact is provided. The method may include depositing, by atomic layer deposition, a passivation layer over at least a region of a metal surface, wherein the passivation layer may include aluminum oxide, and electrically contacting the region of the metal surface with a metal contact structure, wherein the metal contact structure may include copper.

There is provided a bonding wire that improves bonding reliability of a ball bonded part and ball formability and is suitable for on-vehicle devices. The bonding wire for a semiconductor includes a Cu alloy core material, and a Pd coating layer formed on a surface of the Cu alloy core material, and is characterized in that the Cu alloy core material contains Ni, a concentration of Ni is 0.1 to 1.2 wt. % relative to the entire wire, and a thickness of the Pd coating layer is 0.015 to 0.150 m.

There is provided a bonding wire that improves bonding reliability of a ball bonded part and ball formability and is suitable for on-vehicle devices. The bonding wire for a semiconductor includes a Cu alloy core material, and a Pd coating layer formed on a surface of the Cu alloy core material, and is characterized in that the Cu alloy core material contains Ni, a concentration of Ni is 0.1 to 1.2 wt. % relative to the entire wire, and a thickness of the Pd coating layer is 0.015 to 0.150 m.

A wire comprising a wire core with a surface, the wire core having a coating layer superimposed on its surface, wherein the wire core includes: (a) pure silver consisting of silver and further components; or (b) doped silver consisting of silver, at least one doping element, and further components; or (c) a silver alloy consisting of silver, palladium and further components; or (d) a silver alloy consisting of silver, palladium, gold, and further components; or (e) a doped silver alloy consisting of silver, palladium, gold, at least one doping element, and further components, wherein the individual amount of any further component is less than 30 wt.-ppm and the individual amount of any doping element is at least 30 wt.-ppm, and the coating layer is a single-layer of gold or palladium or a double-layer comprised of an inner layer of nickel or palladium and an adjacent outer layer of gold.

A wire comprising a wire core with a surface, the wire core having a coating layer superimposed on its surface, wherein the wire core includes: (a) pure silver consisting of silver and further components; or (b) doped silver consisting of silver, at least one doping element, and further components; or (c) a silver alloy consisting of silver, palladium and further components; or (d) a silver alloy consisting of silver, palladium, gold, and further components; or (e) a doped silver alloy consisting of silver, palladium, gold, at least one doping element, and further components, wherein the individual amount of any further component is less than 30 wt.-ppm and the individual amount of any doping element is at least 30 wt.-ppm, and the coating layer is a single-layer of gold or palladium or a double-layer comprised of an inner layer of nickel or palladium and an adjacent outer layer of gold.

A noble metal-coated silver bonding wire suppresses corrosion at the bonding interface under severe conditions of high temperature and high humidity, and the noble metal-coated silver bonding wire can be ball-bonded in the air. The noble metal-coated silver wire for ball bonding is a noble metal-coated silver wire including a noble metal coating layer on a core material made of pure silver or a silver alloy, wherein the wire contains at least one sulfur group element, the noble metal coating layer includes a palladium intermediate layer and a gold skin layer, the palladium content relative to the entire wire is 0.01 mass % or more and 5.0 mass % or less, the gold content relative to the entire wire is 1.0 mass % or more and 6.0 mass % or less, and the sulfur group element content relative to the entire wire is 0.1 mass ppm or more and 100 mass ppm or less.

A noble metal-coated silver bonding wire suppresses corrosion at the bonding interface even under severe conditions of high temperature and high humidity in automobiles and does not cause energization failure in a semiconductor device in which electrodes of a semiconductor chip and electrodes of lead frames or the like are connected by the bonding wire. The noble metal-coated silver wire for ball bonding wire includes a noble metal coating layer on a core material made of pure silver or a silver alloy, wherein the wire contains at least one sulfur group element, the noble metal coating layer includes at least one palladium layer, the total palladium content relative to the entire wire is 0.01 mass % or more and 5.0 mass % or less, and the total sulfur group element content relative to the entire wire is 0.1 mass ppm or more and 100 mass ppm or less.

A noble metal-coated silver bonding wire suppresses corrosion at the bonding interface even under severe conditions of high temperature and high humidity in automobiles and does not cause energization failure in a semiconductor device in which electrodes of a semiconductor chip and electrodes of lead frames or the like are connected by the bonding wire. The noble metal-coated silver wire for ball bonding wire includes a noble metal coating layer on a core material made of pure silver or a silver alloy, wherein the wire contains at least one sulfur group element, the noble metal coating layer includes at least one palladium layer, the total palladium content relative to the entire wire is 0.01 mass % or more and 5.0 mass % or less, and the total sulfur group element content relative to the entire wire is 0.1 mass ppm or more and 100 mass ppm or less.

Provided is a Pd coated Cu bonding wire for a semiconductor device capable of sufficiently obtaining bonding reliability of a ball bonded portion in a high temperature environment of 175 C. or more, even when the content of sulfur in the mold resin used in the semiconductor device package increases.

The bonding wire for a semiconductor device comprises a Cu alloy core material; and a Pd coating layer formed on a surface of the Cu alloy core material; and contains 0.03 to 2% by mass in total of one or more elements selected from Ni, Rh, Ir and Pd in the bonding wire and further 0.002 to 3% by mass in total of one or more elements selected from Li, Sb, Fe, Cr, Co, Zn, Ca, Mg, Pt, Sc and Y. The bonding wire can be sufficiently obtained bonding reliability of a ball bonded portion in a high temperature environment of 175 C. or more, even when the content of sulfur in the mold resin used in the semiconductor device package increases by being used.

Provided is a Pd coated Cu bonding wire for a semiconductor device capable of sufficiently obtaining bonding reliability of a ball bonded portion in a high temperature environment of 175 C. or more, even when the content of sulfur in the mold resin used in the semiconductor device package increases.

The bonding wire for a semiconductor device comprises a Cu alloy core material; and a Pd coating layer formed on a surface of the Cu alloy core material; and contains 0.03 to 2% by mass in total of one or more elements selected from Ni, Rh, Ir and Pd in the bonding wire and further 0.002 to 3% by mass in total of one or more elements selected from Li, Sb, Fe, Cr, Co, Zn, Ca, Mg, Pt, Sc and Y. The bonding wire can be sufficiently obtained bonding reliability of a ball bonded portion in a high temperature environment of 175 C. or more, even when the content of sulfur in the mold resin used in the semiconductor device package increases by being used.