Recent years, in connection with the rapid spread of portable apparatus, semiconductor apparatus mounted therein is required to be thinner, smaller and lighter. In order to fill this demand, a large number of inventions have been made.
In fabrication of a conventional semiconductor apparatus, a rewiring pattern, which is made of copper (Cu), is electrically connected to electrode pads of a semiconductor device (semiconductor element). The rewiring pattern is connected to conductive posts, which are made of copper (Cu). The semiconductor device is molded with a resin so that the molding resin has an upper surface on the same plane with upper surfaces of the conductive posts. Solder balls are formed on upper ends of the Cu posts, which are exposed from the molding resin.
The above-described process is carried out on a semiconductor wafer, which has a plurality of semiconductor devices. The semiconductor wafer is diced to make individual semiconductor apparatuses. The semiconductor devices are mounted on a circuit board or substrate.
An electrical test is carried out on the semiconductor apparatus mounted on the circuit board. At the same time, the solderability or wetting condition of the solder balls is inspected. Such a solderability or wetting inspection is important to know the mechanical strength of the apparatus, especially when the apparatus is used in a vehicle, in which case it is required to have high reliability. However, according to the above-described conventional semiconductor apparatus, the solder balls are arranged deep inside of the apparatus. As a result, it is difficult to visually recognize the solderability or wetting condition of the solder balls. The very ends of electrodes are easily applied with outside stress, so that solder balls for those electrodes must be connected reliably.
USPTO Backgrounds
USPTO Backgrounds