Observation of peripheral charge induced low frequency capacitance-voltage behaviour in metal-oxide-semiconductor capacitors on Si and GaAs substrates
Loading...
Files
Published Version
Date
2012
Authors
O'Connor, Éamon
Cherkaoui, Karim
Monaghan, Scott
O'Connell, D.
Povey, Ian M.
Casey, P.
Newcomb, Simon B.
Gomeniuk, Yuri Y.
Provenzano, G.
Crupi, Felice
Journal Title
Journal ISSN
Volume Title
Publisher
AIP Publishing
Published Version
Abstract
We report on experimental observations of room temperature low frequency capacitance-voltage (CV) behaviour in metal oxide semiconductor (MOS) capacitors incorporating high dielectric constant (high-k) gate oxides, measured at ac signal frequencies (2 kHz to 1 MHz), where a low frequency response is not typically expected for Si or GaAs MOS devices. An analysis of the inversion regions of the CV characteristics as a function of area and ac signal frequency for both n and p doped Si and GaAs substrates indicates that the source of the low frequency CV response is an inversion of the semiconductor/high-k interface in the peripheral regions outside the area defined by the metal gate electrode, which is caused by charge in the high-k oxide and/or residual charge on the high-k oxide surface. This effect is reported for MOS capacitors incorporating either MgO or GdSiOx as the high-k layers on Si and also for Al2O3 layers on GaAs(111B). In the case of NiSi/MgO/Si structures, a low frequency CV response is observed on the p-type devices, but is absent in the n-type devices, consistent with positive charge (>8 x 10(10) cm(-2)) on the MgO oxide surface. In the case of the TiN/GdSiOx/Si structures, the peripheral inversion effect is observed for n-type devices, in this case confirmed by the absence of such effects on the p-type devices. Finally, for the case of Au/Ni/Al2O3/GaAs(111B) structures, a low-frequency CV response is observed for n-type devices only, indicating that negative charge (> 3 x 10(12) cm(-2)) on the surface or in the bulk of the oxide is responsible for the peripheral inversion effect. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729331]
Description
Keywords
III-V semiconductors , Oxide surfaces , Electrodes , Capacitors , Semiconductor device fabrication
Citation
O’Connor, É., Cherkaoui, K., Monaghan, S., O’Connell, D., Povey, I., Casey, P., Newcomb, S. B., Gomeniuk, Y. Y., Provenzano, G., Crupi, F., Hughes, G. and Hurley, P. K. (2012) 'Observation of peripheral charge induced low frequency capacitance-voltage behaviour in metal-oxide-semiconductor capacitors on Si and GaAs substrates', Journal of Applied Physics, 111(12), 124104 (7pp). doi: 10.1063/1.4729331
Link to publisher’s version
Copyright
© 2012, American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in O’Connor, É., Cherkaoui, K., Monaghan, S., O’Connell, D., Povey, I., Casey, P., Newcomb, S. B., Gomeniuk, Y. Y., Provenzano, G., Crupi, F., Hughes, G. and Hurley, P. K. (2012) 'Observation of peripheral charge induced low frequency capacitance-voltage behaviour in metal-oxide-semiconductor capacitors on Si and GaAs substrates', Journal of Applied Physics, 111(12), 124104 (7pp). doi: 10.1063/1.4729331 and may be found at http://aip.scitation.org/doi/10.1063/1.4729331