E-band radio link communication chipset in cost effective Wafer Level Chip Size Package (WLCSP) technology

Cost effective E-band transmitter and receiver chipset MMIC´s, that use a three-dimensional MMIC technology optimized for flip-chip implementation, are under development. Here, the first edition of MMIC´s successfully designed and fabricated are presented. The MMIC structure incorporates inverse TFMS lines so that a ground metal can be applied to cover the whole chip surface except for interconnect pads. Four metal layers, each of them are covered with polyimide and SiN films. Hence, these MMIC chips require no package, as well as can be directly assembled on printed circuit board. We call this platform Wafer Level Chip Size Package (WLCSP) technology. The E-band transceiver is composed of a novel ultra-wide-band x3 multiplier for LO signal supply to frequency converters. It is a combination of 90°-coupler-based x3 multiplier and buffer amplifiers. The ultra-wide-band amplifier design methodology was extensively applied to other amplifiers. The up- and down-converters are balanced resistive mixers suitable for linear operation. The WLCSP technology was effectively employed to shrink each functional component areas. Each of tripler and converters was implemented in a small area on a 2.3 mm × 1.7 mm die.