Extension of the ADC Charge-Collection Model to Include Multiple Junctions

The ADC charge-collection model was derived for silicon diodes containing a single reverse-biased p-n junction. The present paper extends the model to include two junctions, and the goal is to estimate how collected charge is shared between them. The extended model identifies the conditions needed to produce either of three possibilities. One possibility is that charge is shared by both junctions, and the total collected charge from the two junctions is less than the total amount of liberated charge. A second possibility is that collected charge is shared by both junctions, and the total collected charge from the two junctions is equal to the total amount of liberated charge. The third possibility is that all liberated charge is collected by one junction, and no charge is collected by the other. Examples show excellent agreement with TCAD simulations.