Low Insertion Loss Sub-6GHz Heterogeneous GaN/RF-SOI SPDT Switch for High Power Applications

This paper presents the Radio Frequency (RF) circuit design and characterization of a Single Pole Double Throw (SPDT) switch. The switch is realized in a Gallium Nitride (GaN)/RF-SOI heterogeneous technology using “Micro-transfer-printing”. The measured insertion loss and isolation are respectively below 0.65 dB and -12.7 dB up to 6 GHz. The large signal characterization using a continuous wave shows a hard breakdown at 36 dBm. On the other hand, the pulsed large signal measurement shows a 1dB input compression point of 48 dBm which meets the targeted value. This result confirms that the hard breakdown in CW is due to heat accumulation in the GaN. To address this issue, a heat evacuation technique for future hardware iteration is proposed. This heat evacuation technique should allow to achieve a CP1 of 48 dBm. And so, fully benefit from the advantages from both GaN and RF-SOI technologies on the same chip.