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Modification of MIS structures with thermal SiO2 films by phosphorus diffusion
We investigate the diffusion of phosphorus in thermal SiO2 films of MIS structure and influence
of the process on charge effects in gate dielectric and at interfaces in Fowler–Nordheim high-field
tunnel injection of electrons. One rates the cross sections of electron traps in a phosphosilicate
glass (PSG) film. We show that the density of electron traps increases with increasing the PSG
film thickness. The ability of using a negative charge has been established. It is accumulated in the
PSG film of MIS structures with double-layer SiO2–PSG gate dielectric during high-field tunnel
injection of electrons, to modify MIS devices. It is shown that the use of a double-layer SiO2–PSG
gate dielectric with concentration of phosphorus in PSG film of 0.4–0.9% allows one to increase
the average amount of charge injected into a dielectric until breakdown and decrease the amount
of defective structures with a low amount of charge injected into the dielectric before breakdown.