Cutoff frequency Jr characteristics for AlGaAs/GaAs HBTs with planar structures are studied, by two-dimensional simulation, with an emphasis placed on their dependences on the collector parameters. It is shown that the sub-collector resistance becomes an important factor to achieve a higher fTin the high current region, and so it should be made as low as possible. Effects of introducing semi-insulating external collectors are also studied. It is shown that the introduction of semi-insulating layer is effective to improve the fTcharacteristics provided that it is slightly away from the intrinsic collector region.
|ジャーナル||COMPEL - The international journal for computation and mathematics in electrical and electronic engineering|
|出版ステータス||Published - 1993 4 1|
ASJC Scopus subject areas
- Computer Science Applications
- Computational Theory and Mathematics
- Electrical and Electronic Engineering
- Applied Mathematics