Measurement Strategy and Figure of Merit

The dielectric constant and breakdown field of a material are not the only considerations. Because a capacitor is used for charge storage, the leakage properties of the film are also critical. These are largely controlled by the defects in the films which can include oxygen (anion) vacancies or mixed valence effects in the cations. It is important that films that are as fully oxidized as possible be studied. 

The CCS approach is well matched to the synthesis part of the problem of the identification of new thin-film high dielectric constant materials for embedded DRAM applications. As noted above, low-temperature deposition is essential and the CCS approach provides in situ mixing at low temperatures. Samples are obtained in thin-film form and can be made in thicknesses that are similar to those that will actually be used. 

In a materials search it is essential to distinguish interesting samples from mundane samples. Two considerations are important. First, the measurement technique chosen must provide data that is meaningfully related to the problem under study. Second, the measurement time should be about as rapid as the synthesis step in order for meaningful progress to occur. 

In the case of defining a measurement strategy that bears a meaningful relationship to the property of interest, the aim of the evaluation is to guide the researcher to materials with the most interesting behavior. The initial screen need not be thorough nor definitive but must be indicative. A limited subset of candidate materials 

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