Design and Realization of Bipolar Transistors

The decade of the 1980s has seen remarkable developments in the design and realization of bipolar transistors. In silicon technology the emergence of polysilicon emitters and self-aligned fabrication techniques has resulted in a considerable improvement in the performance of high-speed digital circuits. Similarly, in gallium arsenide technology GaAs/GaA1As heterojunctions have developed to the point that self-aligned MSI circuits can be produced with extremely high performance and also reasonable yields. These innovations will not only lead to large improvements in the switching speed of bipolar circuits but will also open up new applications for bipolar transistors. The purpose of this book is to bring together these new developments into a single text which covers both bipolar transistor design and fabrication. The book will also cover the broader topic of the optimization of bipolar devices and processes for high-speed, digital circuits. This will be achieved through the use of a quasi-analytical expression for the gate delay of an ECL logic gate.