Taiyo Yuden Co Ltd developed a technology to embed a GaAs (gallium arsenide) semiconductor in a printed circuit board and commercialized a device embedded substrate embedded with a GaAs antenna switch.
For the commercialization, Taiyo Yuden cooperated with Panasonic Mobile Communications Co Ltd to, for example, optimize its high-frequency circuit. This product has been employed for some of Panasonic Mobile Communications' mobile phones.
An increasing number of smartphones and tablet computers having communication functions can deal with multiple frequency bands so that high-quality phone call and high-speed wireless communication can be realized. Also, to efficiently use multiple frequency bands, they are equipped with GaAs antenna switches that have excellent high-frequency properties.
It is said that the method of embedding a GaAs antenna switch in a printed circuit board by using a bare chip is effective in reducing the size of a high-frequency circuit. However, with existing device embedded substrates, it is difficult to protect GaAs antenna switches, which have relatively low strengths, from external impacts and to embed them by using bare chips, which require high accuracy.
This time, Taiyo Yuden employed the "Eomin," a device embedded substrate whose rigidity was enhanced by using a copper (Cu) core. Also, it reduced via hole size and Cu line thickness by half, improving the accuracy of component mounting and the reliability of Cu plating.
As a result, the company succeeded in embedding a GaAs antenna switch in a printed circuit board by using a bare chip, which has been considered impossible, and reduced module size and thickness and increased module density.
Taiyo Yuden will exhibit the device embedded substrate in its booth at Ceatec Japan 2011, which will take place from Oct 4, 2011, in Japan.