Nippon Micrometal Corporation

Nippon Steel Chemical & Material Co., Ltd.

Nippon Steel Materials Co., Ltd.

Nippon Steel & Sumikin Materials Co., Ltd.

Akihito Nishibayashi

Takashi Yamada

Tomohiro Uno

Takayuki Kobayashi

Daizo Oda

Teruo Haibara

Tetsuya Oyamada

Keiichi Kimura

Shinichi Terashima

Motoki Eto

There is provided an Al bonding wire which can achieve a sufficient bonding reliability of bonded parts of the bonding wire under a high temperature state where a semiconductor device using the Al bonding wire is operated. The Al bonding wire is characterized in that the wire contains 0.02 to 1% by mass of Fe, further contains 0.05 to 0.5% by mass in total of at least one or more of Mn and Cr, and the balance includes Al and inevitable impurities, wherein a total content of Fe, Mn and Cr in solid solution is 0.01 to 1% by mass. The Al bonding wire contains Mn and Cr in addition to Fe, so that Fe, Mn and Cr can be promoted to form a solid solution in quenching treatment after the solution treatment. Accordingly, the Al bonding wire can achieve an effect of solid-solution strengthening of the wire due to the increase in the total content of Fe, Mn and Cr in solid solution and an effect of preventing recrystallization from proceeding during use of the semiconductor device at a high temperature for a long time.

Al bonding wire

There is provided a metal-coated Al bonding wire which can provide a sufficient bonding reliability of bonded parts of the bonding wire under a high temperature state where a semiconductor device using the metal-coated Al bonding wire is operated. The bonding wire includes a core wire of Al or Al alloy, and a coating layer of Ag, Au or an alloy containing them formed on the outer periphery of the core wire, and the bonding wire is characterized in that when measuring crystal orientations on a cross-section of the core wire in a direction perpendicular to a wire axis of the bonding wire, a crystal orientation <111> angled at 15 degrees or less to a wire longitudinal direction has a proportion of 30 to 90% among crystal orientations in the wire longitudinal direction. Preferably, the surface roughness of the wire is 2 μm or less in terms of Rz.

Bonding wire

There is provided an Al bonding wire which can provide a sufficient bonding reliability of bonded parts of the bonding wire under a high temperature state where a semiconductor device using the Al bonding wire is operated. The bonding wire is composed of Al or Al alloy, and is characterized in that an average crystal grain size in a cross-section of a core wire in a direction perpendicular to a wire axis of the bonding wire is 0.01 to 50 μm, and when measuring crystal orientations on the cross-section of the core wire in the direction perpendicular to the wire axis of the bonding wire, a crystal orientation <111> angled at 15 degrees or less to a wire longitudinal direction has a proportion of 30 to 90% among crystal orientations in the wire longitudinal direction.

It is an object of the present invention to provide a copper-based bonding wire whose material cost is low, having excellent ball bondability, reliability in a heat cycle test or reflow test, and storage life, enabling an application to thinning of a wire used for fine pitch connection. The bonding wire includes a core material having copper as a main component and an outer layer which is provided on the core material and contains a metal M and copper, in which the metal M differs from the core material in one or both of components and composition. The outer layer is 0.021 to 0.12 &#x3bc;m in thickness.

Bonding wire for semiconductor device

Provided is a bonding structure of a bonding wire and a method for forming the same which can solve problems of conventional technologies in practical application of a multilayer copper wire, improve the formability and bonding characteristic of a ball portion, improve the bonding strength of wedge connection, and have a superior industrial productivity. A bonding wire mainly composed of copper, and a concentrated layer where the concentration of a conductive metal other than copper is high is formed at a ball bonded portion. The concentrated layer is formed in the vicinity of the ball bonded portion or at the interface thereof. An area where the concentration of the conductive metal is 0.05 to 20 mol % has a thickness greater than or equal to 0.1 &#x3bc;m, and it is preferable that the concentration of the conductive metal in the concentrated layer should be five times as much as the average concentration of the conductive metal at the ball bonded portion other than the concentrated layer.

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Iruma, Japan

Akihito Nishibayashi