@article{oai:nagoya.repo.nii.ac.jp:00023087,
 author = {Kanematsu, Masayuki and Shibayama, Shigehisa and Sakashita, Mitsuo and Takeuchi, Wakana and Nakatsuka, Osamu and Zaima, Shigeaki},
 issue = {8S2},
 journal = {Japanese Journal of Applied Physics},
 month = {Aug},
 note = {We investigated the effect of GeO2 deposition temperature (T depo) on electronic properties of Al/Al2O3/GeO2/Ge MOS capacitors. Capacitance–voltage characteristics show frequency dispersions under depletion and strong inversion conditions, which can be attributed from the interface states at the atomic layer deposition (ALD)-GeO2/Ge interface and from the defect states in the quasi-neutral region in the Ge substrate, respectively. We found that the interface state density (D it) shows similar values and energy distributions as T depo decreases to 200 from 300 °C, while a higher D it is observed at a T depo of 150 °C. Also, from the temperature dependence of conductance, the frequency dispersion under the strong inversion condition can be related to the minority carrier diffusion to the quasi-neutral region of the Ge substrate. The frequency dependence of conductance reveals that the undesirable increment of the bulk defect density can be suppressed by decreasing T depo. In this study, the bulk defect density in a MOS capacitor prepared at a T depo of 200 °C decreases one tenth compared with that at a T depo of 300 °C. The ALD of GeO2 at a low temperature of around 200 °C is effective for both obtaining a low D it and preventing the undesirable introduction of bulk defect density.},
 pages = {08PC05--08PC05},
 title = {Effect of GeO2 deposition temperature in atomic layer deposition on electrical properties of Ge gate stack},
 volume = {55},
 year = {2016}
}