A new degradation phenomenon on thin gate oxide PMOSFETs with BF2 implanted p+-poly gate has been demonstrated and investigated. The cause of this type degradation is a combination of the boron penetration through the gate oxide and charge trap generation due to presence of fluorine in the gate oxide and some other processing-induced effects. The negative charge-induced degradation other than enhanced boron diffusion has been studied in detail here. The impact of this process-sensitive p+-poly gate structure on deep submicron CMOS process integration has been discussed.
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