15 GHz f_max microwave silicon p-n- rho transistors with single-crystal emitters fabricated with simple four mask process

Vertical p-n- rho transistors have been fabricated using a four mask, low cost quasi-selfaligned process with submicrometre feature sizes. The resulting monocrystalline emitter devices achieve f_t greater than 9 GHz and f_max greater than 15 GHz with BV_ceo greater than 13 V. These discrete p-n- rho 's were used successfully as active loads for a monolithic n- rho -n opamp to achieve a gain-bandwidth product of 4.4 GHz.