The injection model-a structure-oriented model for merged transistor logic (MTL)

The merged transistor device is represented by assigning separate diodes to the various electron and hole injections along the active p-n junction. Where collection takes place, current sources are introduced. Measurement procedures are described that allow a quantitative separation of the various injections, and hence the determination of the model parameters. Results of such measurements are given. Device terminal parameters, like current gains and storage time constants, can be predicted from the measurements for devices of arbitrary horizontal geometry, so that the injection model can serve as a device optimization tool. As a circuit analysis model it allows representation of the internal device series resistances which would not be possible with an Ebers-Moll model. The injection model is significant beyond the merged transistor logic (MTL) aspects as it renders a better insight into bipolar devices, particularly into lateral p-n-p and saturated n-p-n transistors.