Advancements in bipolar VLSI circuits and technologies

This paper gives an overview on bipolar circuit/device techniques for VLSI logic and memories. Due to their inherent speed advantage over FETs, bipolar circuits are widely used for high-performance masterslice and custom logic and for high-speed static memory arrays. For logic, traditional circuits such as transistor-transistor logic (TTL) and emitter-coupled logic (ECL) are still mainly applied, but also new circuit technologies such as integrated injection logic or merged transistor logic (I2L/MTL) and Schottky transistor logic (STL) or integrated Schottky logic (ISL) have been devised to manage the VLSI technology constraints. For high-speed memory applications such as caches, local stores, or registers, conventional memory cells are increasingly replaced by more advanced memory devices allowing higher bit densities and lower power dissipation. Significant progress can be expected by technology extensions such as dielectric isolation, multilayer metallization, and polysilicon techniques, in addition to shrinking the devices to 1 micron dimensions or below. Some experimental data and projections indicate the strong potentials of bipolar VLSI.