Title :
Extraction of base and emitter series resistances from the net transadmittance parameter
Author :
Cai, Will Z. ; Shastri, Sudhama
Author_Institution :
ON Semicond. Corp., Phoenix, AZ, USA
fDate :
4/1/2005 12:00:00 AM
Abstract :
We report a new high-frequency technique for extracting base and emitter resistances (Rbb and Re, respectively) of a bipolar junction transistor. We highlight, for the first time, the physical significance of the net transadmittance parameter (y12-y21) as a figure of merit for the transistor´s intrinsic performance. We report that while Real(y12-y21) increases monotonically with frequency, Imag(y12-y21) exhibits a peak in the GHz range. This peak is attributed to competition between the obstruction of signals as a result of the base-collector capacitance, and the shunt path to ground. We have proven, both theoretically and experimentally, that -1/Real(y12-y21) is linearly proportional to ω2 with a y-intercept of 1/gm+Re+Rbb/βdc. By combining this result with the Basaran-Berroth method, individual values of Re and Rbb are extracted and plotted as a function of Vbe. Data from transistors with various emitter lengths further validate the efficacy of this extraction technique.
Keywords :
S-parameters; bipolar transistors; electric admittance; electric resistance; microwave technology; Basaran-Berroth method; S-parameters; base series resistance; base-collector capacitance; bipolar junction transistor; emitter length; emitter series resistance; extraction technique; gigahertz range; high-frequency technique; hybrid-π model; net transadmittance parameter; shunt path; signal obstruction; Admittance; Bipolar transistors; Capacitance; Data mining; Electrical resistance measurement; Equivalent circuits; Frequency; Parameter extraction; Scattering parameters; Voltage; Base resistance; S-parameters; bipolar transistor; hybrid-;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2005.844790