Properties of integrated injection logic fabricated under different process conditions

Nonoptimised, conventional I2L can be fabricated in processes established for other types of logic, or those for analogue circuitry. These processes vary widely in the properties of epilayer, base doping and other process parameters. To explain I2L behaviour in such processes, the static and dynamic properties of I2L have been investigated over a wide range of epilayer doping concentration and thickness, active base resistivity etc. Some previous apparent contradictions about the n-p-n base current components are resolved. In addition it is demonstrated that the power-delay product at low injector current is not, in general, constant. Also, the dependence of intrinsic gate delay on epilayer doping is found to deviate from theoretical predictions. Possible reasons for the discrepancies are discussed.