Semiconductor device with copper wire ball bonding
Abstract
Abstract A semiconductor device in accordance with the present invention includes a semiconductor chip which is bonded to a die pad using a solder having a liquidus temperature of 370° C. or less. A copper ball is moved to contact an Al electrode pad on the semiconductor chip in less than 150 ms after formation of the ball. Plastic deformation takes place so that the copper ball is pressed against the aluminum electrode pad and the height of the copper ball becomes 25 μm or less. It is possible to firmly wire the Al pad on the semiconductor chip and the inner lead frame without cracking the glass coating by utilizing a silver plating on the die pad and an Au-metallized layer on the rear side of the semiconductor chip. It is also possible to decrease the work hardening property of the Cu ball and prevent Al exudation when the Cu ball is bonded to the Al electrode pad.
Inventors
- 👤 Kiyoaki Tsumura
Bibliographic Details
Claims Analysis
Total Claims: 10References Cited (Backward Citations)
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