Ka-band 2-stacked chip-scale-package using GaAs PA MMIC with hot-via interconnections for spacecraft applications

This paper demonstrates fundamental evaluation results of a 2-stacked chip-scale-packaged (CSP) power amplifier (PA) operating at Ka-band for high data rate communication inside of future reusable rockets. The PA monolithic microwave integrated circuit (MMIC) is fabricated by 0.15 μm GaAs high-electron mobility transistor (HEMT) process having hot-via interconnection structure. The proposed CSP has 2-stacked PA MMICs structure. RF signals are simply divided by the hot-via interconnection to the two MMCIs as well as DC biases. Measurement results of the proposed CSP show the gain and P1dB of 15.7 dB and 14.6dBm at 33.0 GHz, respectively. Comparing with non-stacked structure, the proposed CSP has 2.6 dB increment of P1dB while theoretical increment value is 3 dB. The proposed CSP is feasible to be used as a PA inside a future reusable rocket communication.