A 1-chip RF transceiver MMIC for ETC with surface via-hole isolation technique

An RF Transmitter Receiver MMIC (TX-RX MMIC) with 16-pin plastic package has been developed for 5.8 GHz Japanese Electronic Toll Collection system (ETC). The MMIC contains following RF blocks; local buffer amplifier, variable attenuator, ASK modulator, power amplifier, low-noise amplifier, down-converter, local switch and antenna switch. We have developed the new Surface Via-Hole (SVH) isolation technique to integrate all RF circuits into single chip. The double hetero-junction modulation doped FETs (MODFETs) and SrTiO/sub 3/ (STO) MIM capacitors are also developed to realize a single voltage operation and small chip size. By using SVH isolation technique, low carrier leakage of -43 dBm, high on/off ratio of 39.6 dB at 5.84 GHz and low total current of 150 mA are achieved, and the practical small chip size (2.25/spl times/1.25 mm/sup 2/) is realized.