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AssigneeHitachi, Ltd.
InventorsHanae Shimokawa, Tasao Soga, Hiroaki Okudaira, Toshiharu Ishida, Tetsuya Nakatsuka, Yoshiharu Inaba, Asao Nishimura
Estimating the term…
Provided are a bonded structure by a lead-free solder and an electronic article comprising the bonded structure. The bonded structure has a stable bonding interface with respect to a change in process of time, an enough strength and resistance to occurrence of whiskers while keeping good wettability of the solder. In the bonded structure, a lead-free Sn—Ag—Bi alloy solder is applied to an electrode through an Sn—Bi alloy layer. The Sn—Bi alloy, preferably, comprises 1 to 20 wt % Bi in order to obtain good wettability of the solder. In order to obtain desirable bonding characteristics having higher reliability in the invention, a copper layer is provided under the Sn—Bi alloy layer thereby obtaining an enough bonding strength.
A semiconductor device with a lead, wherein the lead has an Sn—Bi alloy layer comprising 1 to 5 wt % Bi thereon.
A semiconductor device with a lead, wherein an Sn—Bi alloy layer, which comprises from 1 to 5 wt % Bi, is formed on the lead.
A semiconductor device with a lead, wherein an Sn—Bi alloy layer, which comprises from 1 to 5 wt % Bi, is formed directly on the lead.
A semiconductor device with a lead, wherein the lead includes an Sn—Bi alloy layer comprising 1 to 5 wt % Bi as a surface layer.
A semiconductor device with a lead, wherein an Sn—Bi alloy layer, which comprises from 1 to 5 wt % Bi, is formed directly on the lead as a surface layer.
Dependencies are inferred from the claim text.