Self-Heating of Submicron InP/InGaAs DHBTs

We studied the thermal properties of submicron InP/InGaAs/InP double heterojunction bipolar transistors (DHBTs) with emitter dimensions of A=0.25 x 4 mum3. From the temperature dependence of Vbe, we measured a thermal resistance of Rth=3.3 0Cmum2/mW for DHBTs with ion-implanted n+-InP sub-collector at room temperature, compared to a high Rth=7.5 0C mum2/mW from DHBTs with conventional InGaAs sub-collector. Two-dimensional device simulations confirm the measured results.