Semiconductor device, power amplifier device and PC card

A power amplifier device having one or a plurality of amplification systems,

• wherein said amplification system has a semiconductor chip in which a transistor is formed and a plurality of external electrode terminals,
• wherein said external electrode terminals are an input terminal to which a signal to be amplified is supplied, an output terminal for outputting the amplified signal, and first, second, and third power source terminals,
• wherein said transistor is electrically connected between said input terminal and said output terminal,
• wherein electrodes of said transistor are a control electrode connected to said input terminal and said third power source terminal, a first electrode connected to said output terminal and said first power source terminal, and a second electrode connected to said second power source terminal serving as an earth terminal,
• wherein over a top face of said semiconductor chip, an electrode pad corresponding to said external electrode terminal and a plurality of electrode pads formed in a portion of said second electrode of said transistor are provided,
• wherein a conductive wire for electrically connecting said external electrode terminal with said electrode pad corresponding to the external electrode terminal, and a conductive wire for electrically connecting the plurality of electrode pads formed in the portion of said second electrode of said transistor with said second power source terminal are provided,
• wherein each of said electrodes of said transistor is constructed by a base portion and a plurality of fingers projected in a direction orthogonal to said base portion, one of the fingers of said first electrode is disposed between two neighboring fingers of said second electrode,
• wherein said second electrode is connected to a fixed potential, and
• wherein a width of each of said fingers positioned at both ends of said second electrode is wider than a width of each of said fingers positioned between said both ends.