We are modeling the collection process of ionizing radiation created carriers. We assume that the charge collection problem can be reduced to the classical transport of minority carriers, and use the Monte Carlo method to solve the transport equation. This technique, with modest computational requirements, is capable of handling the realistic charge collection environments found in integrated circuits. To test the simulated results, we carried out charge collection experiments on simple layouts to a-particle radiation. Although a small deviation was found from the assumed classical transport, with a slight modification on the simulation this effect could be taken into account. The final agreement between theory and experiment is excellent. Copyright © 1980 by The Institute of Electrical and Electronics Engineers, Inc.