SURFACE-REACTIONS DURING THE A-SI-H GROWTH IN THE DIODE AND TRIODE GLOW-DISCHARGE REACTORS

This paper deals with the simulation of the surface reactions during the hydrogenated amorphous silicon growth using a SiH4 glow discharge plasma in both the triode and diode configurations. The triode system allows us to select the radicals species involved in the growth. Indeed, only the radicals with a long life-time in the gaseous phase can reach the substrate. We have investigated both the substrate temperature and the flux density dependences of both the deposition rate DR and the loss probability-beta. In the triode system, the growth of the film occurs via a precursor state for SiH3 over the top surface. In the diode system, we have to consider another kind of radical with a high reactivity on the surface such as Si2H4. In this case, a direct chemisorption process for a Si2H4-like radical must be taken into account.