Plane structure hetero-junction bipolar transistor - is esp. for HF types and has doped emitter definition zone
Реферат: The bipolar transistor has an emitter - base heterojunction in a plane or quasi - plane structure, esp. those operating at very high frequencies. The base contact(10) is positioned directly on the emitter layer(4') which is defined laterally by a p+ doped possibly zinc region(11) connecting the contact to the base layer by a low resistance bridge. The free carrier concentration is 1020 atoms. cm-3 close to the surface, diffusion being localised under the base contact due to a preliminary deposition at the element surface due to photo-lithographically created windows in the diffusion mask. Lateral limitation of the transistor is by proton-bombardment or chemical etching at the end of the fabrication process. Loss current resulting from polarisation of the lateral diode (LD) is minimised by recombination at the level of a Ga.Al homodiode.
Parasitic pnp bipolar transistor in a silicon-germanium bicmos process
Номер патента: US20120061793A1. Автор: Wensheng QIAN,Donghua Liu. Владелец: Individual. Дата публикации: 2012-03-15.