Characterization, parameter identification, and modeling of a new monolithic emitter-switching bipolar transistor

This paper proposes the characterization, parameter estimation, and modeling of a monolithic cascode, which has been called emitter-switching bipolar transistor (ESBT), suitable for high-voltage applications. Such an innovative device is composed of a high-voltage power bipolar junction transistor (BJT) and low-voltage power MOSFET that are connected in cascode connection, with the MOSFET drain embedded inside the BJT emitter. Being a four-terminal device, the ESBT requires a suitable characterization procedure aimed to identify the main electrical parameters relative to the inner BJT and MOSFET parts. Various test configurations that are needed to characterize the ESBT are presented and discussed. The device has been characterized to derive a behavioral model implemented in the PSpice simulator in order to predict the device performances. The storage-time behavior has been investigated aiming to derive a suitable model devoted to the turn off switching of the ESBT. Such a model gives satisfactory results as long as the storage time and the slope of the collector voltage during the turn off switching are concerned. The full dependence on the temperature has been provided in the presented model by analyzing the thermal behavior of the ESBT from the standpoint view of the static and dynamic characteristics.