Future work

On the other hand, the N2O and O2 plasma treatment also provide a good effect on electrical characteristics although most samples are still worse than that of N2

plasma treatment. The reason is that the samples using N2O and O2 plasma treatment will introduce oxygen bonding to from additional interfacial layer so that the capacitance will be decreased. But for another hand, the thicker oxidation layer becomes a good resistance against leakage current even if the plasma damage has begun to occur. Therefore, we can find that these samples show lower leakage current at the process conditions of 3 min and 5 min even if their capacitance has been seriously degraded by plasma damage.

Finally, in this thesis, the point we focus on is the improvement of capacitance.

The treatment of N2 plasma for 1 min is the best condition because the capacitance has 50% increasing. Simultaneously, its reliability also represents a excellent progress.

The most suitable way for post -deposition treatment by plasma to improve electrical characteristics on MIS structure is observed

5.2 Future work

In this experiment, the HfO2 film was deposited by sputter and furnace system. In

the future, the ALCVD ( Atomic Layer CVD ) system will become another important deposition technology. Further experiment and analysis are required to clarify if the treatment condition is also suitable for ALCVD film. On the other hand, the MOSFET will be fabricated by the same treatment condition to verify the effect on device characteristics, such as mobility, subthreshold swing, and transonductance.

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Table

Table 1-1 High-performance Logic Technology Requirements Roadmap.

( ITRS：2005 updae )