Study Of Monte Carlo Simulation Of The Ionization Damage Of MOS Device

Based on successful inventions and developments of Si materials, transistors and ICs since the middle of the last century, semiconductor materials have become high-tech industrial base materials of the information society in the 21st century. It affects profoundly the world political and economic situation and military confrontation form, and also changes completely people's life style. High-energy photons can induce ionizing radiation effect, and produce large amounts of energy deposition in semiconductor materials, and further cause great ionizing damage for semiconductor devices working in this environment. For MOS type device, ionizing radiation can produce positive charges and interface states in its oxidation layer so as to cause a threshold voltage drift. This influences greatly the application of semiconductors. In the research of high-energy photons transport in semiconductor materials, appropriate computer simulation is usually more economic, quick and reliable than experimental study, so now, most scholars are using Monte Carlo simulation method both at home and abroad.In this paper based on high-energy photons cross-section database, a Monte Carlo simulation code was written with C programming language, using the code the reaction process of high-energy photons in SiO2 layer of MOS device was simulated. The obtained results show that the ionization damage of MOS device has direct relationship with SiO2 thickness, and the reduction of its thickness can significantly reduce the energy deposition in SiO2, and further reduce primary threshold voltage drift and ionization damage of MOS.