Recently, mobile communication terminals including a portable telephone, a personal handy-phone system (PHS), etc. are requested to be smaller and smaller in size. In order to meet this request, a package of semiconductor device employed in the mobile communication terminals is to be downsized.
A conventional semiconductor device is described by referring to FIG. 5. FIG. 5 is a plan view of the conventional semiconductor device having a mini-package with six terminals. The mini-package stores a semiconductor chip. A lead frame 2 is disposed at the center of the package 1, signal terminal electrodes 3 through 7 are disposed on the edges of the package 1. A semiconductor chip 8 is mounted on the lead frame 2. Chip electrodes 9 through 13 disposed on the semiconductor chip 8 are coupled to the signal terminal electrodes 3 through 7 with wires 15 respectively. A chip electrode 14 disposed on the semiconductor chip 8 is coupled to the lead frame 2 with the wire 15. A clearance between the adjacent signal terminal electrodes 4, 5 and 6 is 0.5 mm each.
In the above conventional semiconductor device, when a package is requested to be downsized, the clearance between the adjacent signal terminal electrodes such as the signal terminal electrodes 4 and 5 is considered to be narrowed.
On the other hand, when the semiconductor device is worked at a high frequency, the signal terminal electrodes must be electrically separated with each other, in other words, an isolation between the signal terminal electrodes should be strictly maintained. The clearance between the adjacent signal terminal electrodes thus needs a predetermined distance. When the isolation of -30 dB is required, the clearance must be no less than 0.5 mm.
Accordingly, in the above conventional semiconductor device, the two goals, i.e. downsizing and isolation are not satisfied simultaneously.
USPTO Backgrounds
USPTO Backgrounds