19 mW/μm2 and 24.5 % PAE at 94 GHz for 0.30-μm Transferred InP/GaAsSb DHBT on Si-HR
Résumé
InP HBT technology is a suitable candidate for the future 6G networks that require very high bandwidth. It has already demonstrated high-frequency operation with fmax exceeding 1 THz [1]. However, this performance comes at the cost of aggressive scaling which increases thermal resistance (Rth) due to device narrowing and leads to self-heating limiting overall performance. Transferring InP DHBT to a high-thermal-conductivity substrate has shown a drastic reduction of Rth by 65% on Si-HR [2] and 75% on SiC [3] thanks to their superior heat dissipation properties however its effect on output power remains unexplored. We present continuous wave (CW) large-signal load-pull measurements at 94 GHz of a transferred InP/GaAsSb DHBT transistor fabricated on a high-resistivity silicon substrate (HR-Si). The characterized device features an emitter area of 0.29×4.9μ m2 and was biased for both maximum output power and maximum power-added-efficiency (P.A.E). A peak output power of 14.25dBm(18,84 mW/μm2) was achieved. This result demonstrates the impact of thermal dissipation in reducing self-heating and enabling higher output power.