Submicron Double Heterojunction Bipolar Transistors on Indium Phosphide‐on‐Silicon
Rita Younes, Abdelmalek Zemour, Christophe Coinon, Malek Zegaoui, Yannick Roelens, Pascal Chevalier, Bruno Ghyselen, Mohammed ZaknouneABSTRACT
In this work, we report the fabrication and characterisation of an InGaAs/InP double heterojunction bipolar transistor (DHBT) on an indium phosphide‐on‐silicon (InPoSi) substrate. The device exhibits a DC current gain of 65. Dynamic measurements performed on a submicron 0.35 × 3 µm 2 device further confirm its high‑frequency capability, with a current‑gain cutoff frequency ( f T ) of 200 GHz and a maximum oscillation frequency ( f max ) of 90 GHz, indicating its suitability for high‑frequency applications and the strong potential of the InPoSi platform for high‑performance bipolar technologies. Thermal resistance ( R TH ) was extracted for a device with an area of 0.5 × 10 µm 2 , yielding a value of 5867 K/W, which is approximately 2.5 times higher than that of a standard DHBT on its own InP substrate with the same topology. This result provides important insight into the thermal management challenges associated with InPoSi‐based DHBTs.