Daigo Suzuki

3D-integrated, low-height, small module design techniques for 4.48GHz, 560MHz-bandwidth TransferJet™ transceiver

A low-height, small module for 4.48GHz carrier frequency, 560MHz bandwidth transceiver has been designed employing 3D integration technology. An LSI integrated with RF and digital baseband circuits is embedded in an organic resin substrate of the module to achieve a small module size of 4.8mm × 4.8mm × 1.0mm. Since RF signals are degraded by parasitic capacitance associated with the low height and small footprint of the module, three design techniques are proposed in the paper. The module realizes the worlds smallest size, and achieves sufficient transmitter modulation accuracy and receiver sensitivity, which meet TransferJet™ standards.

Ultrathin 4-layer flexible printed circuits (FPC) fabricated by molecular bonding technology

We have developed the ultrathin 4-layer flexible printed circuits (FPCs) with the thickness of 135 um. This 135 um ultrathin 4-layer FPC is made by the molecular bonding technology, by which the electroless plating (metallizing) can be directly applied to polyimide (PI) by using molecular junction agents. In this study, we show the fabrication procedures, the mechanism of direct copper plating, and the reliability verification of the ultrathin 4-layer FPC prototype.