Interface modification by irradiation with alpha particles

Abstract

The performance of electronic devices and systems get degraded when they are exposed to radiation above a certain limit or over longer duration and the process is called radiation damage. The performance degradation is due to the damage caused to the interface by the radiation. The damage takes place in the form of dangling or unsatisfied bonds and, trapped charges, formed at the interface. Interfaces and surfaces cannot be ignored and are indispensable in many problems like creation of numerous semiconductor junctions while forming devices, in chemical reactions, intricate biological reactions and processes, and corrosions of material surfaces etc. Substrate surfaces and interface of substrates and oxides play a key role in the performance of the metal oxide/insulator semiconductor field effect transistor and various other similar types of devices. Surfaces are abrupt termination of one material and formation of a second material so the surfaces may have unsaturated chemical bonds forming chemically active surfaces. Even after growing a thin layer of other required material over it, all the unsaturated chemical bonds are not satisfied. Later these surfaces with unsaturated bonds play an important role in the performance reliability of the semiconductor devices. Annealing is one of the processes that is used to modify these unsaturated dangling bonds. This investigation is to explore the possibility of interface modification by alpha particle irradiation, after the fabrication of the interfaces/devices. Here we present a method to improve the interface of silicon and hafnium dioxide, through alpha particle irradiation. This method can be used to improve the interface quality even after fabrication process is over.