ABSTRACT
Capacitance-Voltage (C-V) characterization and hard x-ray photoelectron spectroscopy (HAXPES) measurements have been used to study metal/Al2O3/In0.53Ga0.47As capacitor structures with high (Ni) and low (Al) work function metals. The HAXPES measurements observe a band bending occurring prior to metal deposition, which is attributed to a combination of fixed oxide charges and interface states of donor-type. Following metal deposition, the Fermi level positions at the Al2O3/In0.53Ga0.47As interface move towards the expected direction as observed from HAXPES measurements. The In0.53Ga0.47As surface Fermi level positions determined from both the C-V analysis at zero gate bias and HAXPES measurements are in reasonable agreement. The results are consistent with the presence of electrically active interface states at the Al2O3/In0.53Ga0.47As interface and suggest an interface state density increasing towards the In0.53Ga0.47As valence band edge.
ACKNOWLEDGMENTS
The authors from Tyndall National Institute and Dublin City University acknowledge Science Foundation Ireland for financial support of the research work through the INVENT Project (SFI/09/IN.1/I2633). The central fabrication facility at Tyndall is acknowledged for the fabrication of the experimental samples used in this work. Ian Povey from Tyndall is acknowledged for the ALD growth of the Al2O3 layers. Dan O'Connell from Tyndall is acknowledged for the metallisation. Patrick Carolan from Tyndall is acknowledged for the TEM analysis. Access to the X24A HAXPES beamline at Brookhaven National Laboratory was obtained through a General User Proposal. Use of the National Synchrotron Light Source, Brookhaven National Laboratory, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886.
REFERENCES
- 1. B. Shin, J. R. Weber, R. D. Long, P. K. Hurley, C. G. Van de Walle, and P. C. McIntyre, “ Origin and passivation of fixed charge in atomic layer deposited aluminum oxide gate insulators on chemically treated InGaAs substrates,” Appl. Phys. Lett. 96, 152908 (2010). https://doi.org/10.1063/1.3399776, Google ScholarScitation, ISI
- 2. J. Lin, Y. Y. Gomeniuk, S. Monaghan, I. M. Povey, K. Cherkaoui, É. O'Connor, M. Power, and P. K. Hurley, “ An investigation of capacitance-voltage hysteresis in metal/high-k/In0.53Ga0.47As metal-oxide-semiconductor capacitors,” J. Appl. Phys. 114, 144105 (2013). https://doi.org/10.1063/1.4824066, Google ScholarScitation
- 3. G. Brammertz, H. C. Lin, M. Caymax, M. Meuris, M. Heyns, and M. Passlack, “ On the interface state density at In0.53Ga0.47As/oxide interfaces,” Appl. Phys. Lett. 95, 202109 (2009). https://doi.org/10.1063/1.3267104, Google ScholarScitation, ISI
- 4. E. H. Nicollian and J. R. Brews, MOS Physics and Technology ( Wiley, New York, 2003). Google Scholar
- 5. S. M. Sze and K. K. Ng, Physics of Semiconductor Devices ( Wiley, NJ, 2007). Google Scholar
- 6. É. O'Connor, R. D. Long, K. Cherkaoui, K. K. Thomas, F. Chalvet, I. M. Povey, M. E. Pemble, P. K. Hurley, B. B. Brennan, G. Hughes, and S. Newcomb, “ In situ H2S passivation of In0.53Ga0.47As/InP metal-oxide-semiconductor capacitors with atomic-layer deposited HfO2 gate dielectric,” Appl. Phys. Lett. 92, 022902 (2008). https://doi.org/10.1063/1.2829586, Google ScholarScitation
- 7. R. D. Long, É. O'Connor, S. B. Newcomb, S. Monaghan, K. Cherkaoui, P. Casey, G. Hughes, K. K. Thomas, F. Chalvet, I. M. Povey, M. E. Pemble, and P. K. Hurley, “ Structural analysis, elemental profiling, and electrical characterization of HfO2 thin films deposited on In0.53Ga0.47As surfaces by atomic layer deposition,” J. Appl. Phys. 106, 084508 (2009). https://doi.org/10.1063/1.3243234, Google ScholarScitation
- 8. R. D. Long, B. Shin, S. Monaghan, K. Cherkaoui, J. Cagnon, S. Stemmer, P. C. McIntyre, and P. K. Hurley, “ Charged defect quantification in Pt/Al2O3/In0.53Ga0.47As/InP MOS capacitors,” J. Electrochem. Soc. 158, G103 (2011). https://doi.org/10.1149/1.3545799, Google ScholarCrossref
- 9. É. O'Connor, B. Brennan, V. Djara, K. Cherkaoui, S. Monaghan, S. B. Newcomb, R. Contreras, M. Milojevic, G. Hughes, M. E. Pemble, R. M. Wallace, and P. K. Hurley, “ A systematic study of (NH4)2S passivation (22%, 10%, 5%, or 1%) on the interface properties of the Al2O3/In0.53Ga0.47As/InP system for n-type and p-type In0.53Ga0.47As epitaxial layers,” J. Appl. Phys. 109, 024101 (2011). https://doi.org/10.1063/1.3533959, Google ScholarScitation, ISI
- 10. R. Engel-Herbert, Y. Hwang, and S. Stemmer, “ Comparison of methods to quantify interface trap densities at dielectric/III–V semiconductor interfaces,” J. Appl. Phys. 108,124101 (2010). https://doi.org/10.1063/1.3520431, Google ScholarScitation
- 11. P. K. Hurley, É. O'Connor, S. Monaghan, R. D. Long, A. O'Mahony, I. M. Povey, K. Cherkaoui, J. MacHale, A. J. Quinn, and G. Brammertz, “ Structural and Electrical Properties of HfO2/n-InxGa1−xAs structures (x: 0, 0.15, 0.3 and 0.53),” Electrochem. Soc. Trans. 25(6), 113–127 (2009) https://doi.org/10.1149/1.3206612. Google ScholarCrossref
- 12. L. A. Walsh, G. Hughes, J. Lin, P. K. Hurley, T. P. O'Regan, E. Cockayne, and J. C. Woicik, “ Hard x-ray photoelectron spectroscopy and electrical characterization study of the surface potential in metal/Al2O3/GaAs(100) metal-oxide-semiconductor structures,” Phys. Rev. B 88(4), 045322 (2013). https://doi.org/10.1103/PhysRevB.88.045322, Google ScholarCrossref
- 13. D. R. Lide, CRC Handbook of Chemistry and Physics ( CRC, Boca Raton, 2007). Google Scholar
- 14. K. Kakushima, K. Okamoto, K. Tachi, J. Song, S. Sato, T. Kawanago, K. Tsutsui, N. Sugii, P. Ahmet, T. Hattori, and H. Iwai, “ Observation of band bending of metal/high-k Si capacitor with high energy x-ray photoemission spectroscopy and its application to interface dipole measurement,” J. Appl. Phys. 104, 104908 (2008). https://doi.org/10.1063/1.3021461, Google ScholarScitation
- 15. K. Kobayashi, “ Hard x-ray photoemission spectroscopy,” Nucl. Instrum. Methods Phys. Res., Sect. A 601(1–2), 32–47 (2009). https://doi.org/10.1016/j.nima.2008.12.188, Google ScholarCrossref
- 16. L. A. Walsh, G. Hughes, P. K. Hurley, J. Lin, and J. C. Woicik, “ A combined hard x-ray photoelectron spectroscopy and electrical characterisation study of metal/SiO2/Si(100) metal-oxide-semiconductor structures,” Appl. Phys. Lett. 101, 241602 (2012). https://doi.org/10.1063/1.4770380, Google ScholarScitation
- 17. Y. Y. Gomeniuk, A. N. Nazarov, S. Monaghan, K. Cherkaoui, E. O'Connor, I. Povey, V. Djara, and P. K. Hurley, “ Electrical Properties of High-k Oxide in Pd/Al2O3/InGaAs Stack,” in Proceedings of the International Conference on Nanomaterials: Applications and Properties (2012), Vol. 1, No. 3, p. 03TF16. Google Scholar
- 18. S. Tanuma, C. J. Powell, and D. R. Penn, “ Calculations of electron inelastic mean free paths. IX. Data for 41 elemental solids over the 50 eV to 30 keV range,” Surf. Interface Anal. 43(3), 689–713 (2011). https://doi.org/10.1002/sia.3522, Google ScholarCrossref
- 19. J. Chastain and J. F. Moulder, Handbook of X-ray Photoelectron Spectroscopy: A Reference Book of Standard Spectra for Identification and Interpretation of XPS Data ( Physical Electronics, Eden Prairie, Minnesota, 1995). Google Scholar
- 20. A. Bahari, P. Morgen, and Z. S. Li, “ Valence band studies of the formation of ultrathin pure silicon nitride films on Si(100),” Surf. Sci. 600(15), 2966–2971 (2006). https://doi.org/10.1016/j.susc.2006.05.017, Google ScholarCrossref
- 21. M. Gaowei, E. M. Muller, A. K. Rumaiz, C. Weiland, E. Cockayne, J. Jordan-Sweet, J. Smedley, and J. C. Woicik, “ Annealing dependence of diamond-metal Schottky barrier heights probed by hard x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 100, 201606 (2012). https://doi.org/10.1063/1.4718028, Google ScholarScitation, ISI
- 22. G. Brammertz, H. C. Lin, K. Martens, A. Alian, C. Merckling, J. Penaud, D. Kohen, W.-E. Wang, S. Sioncke, A. Delabie, M. Meuris, M. Caymax, and M. Heyns, “ Electrical properties of III–V/oxide interfaces,” Electrochem. Soc. Trans. 19(5), 375–386 (2009) https://doi.org/10.1149/1.3119560. Google ScholarCrossref
- 23. D. Varghese, Y. Xuan, Y. Q. Wu, T. Shen, P. D. Ye, and M. A. Alam, “ Multi-probe interface characterization of In0.65Ga0.35As/Al2O3 MOSFET,” in Proceedings of International Electron Devices Meeting Technical Digest (2008), pp. 379–382. Google Scholar
- 24. É. O'Connor, S. Monaghan, R. D. Long, A. O'Mahony, I. M. Povey, K. Cherkaoui, M. E. Pemble, G. Brammertz, M. Heyns, S. B. Newcomb, V. V. Afanas'ev, and P. K. Hurley, “ Temperature and frequency dependent electrical characterization of HfO2/InxGa1−xAs interfaces using capacitance-voltage and conductance methods,” Appl. Phys. Lett. 94, 102902 (2009). https://doi.org/10.1063/1.3089688, Google ScholarScitation, ISI
- 25. N. Taoka, M. Yokoyama, S. H. Kim, R. Suzuki, R. Iida, S. Lee, T. Hoshii, W. Jevasuwan, T. Maeda, T. Yasuda, O. Ichikawa, N. Fukuhara, M. Hata, M. Takenaka, and S. Takagi, “ Impact of Fermi level pinning inside conduction band on electron mobility of InxGa1–xAs MOSFETs and mobility enhancement by pinning modulation,” in Proceedings of the IEEE International Electron Devices Meeting (IEDM) ( IEEE, 2001), p. 610. Google Scholar
- 26. H. C. Lin, W. E. Wang, G. Brammertz, M. Meuris, and M. Heyns, “ Electrical study of sulfur passivated In0.53Ga0.47As MOS capacitor and transistor with ALD Al2O3 as gate insulator,” Microelectron. Eng. 86(7–9), 1554–1557 (2009). https://doi.org/10.1016/j.mee.2009.03.112, Google ScholarCrossref
- 27. C. A. Lin, H. C. Chiu, T. H. Chiang, T. D. Lin, Y. H. Chang, W. H. Chang, Y. C. Chang, W. E. Wang, J. Dekoster, T. Y. Hoffmann, M. Hong, and J. Kwo, “ Attainment of low interfacial trap density absent of a large midgap peak in In0.2Ga0.8As by Ga2O3, Gd2O3 passivation,” Appl. Phys. Lett. 98, 062108 (2011). https://doi.org/10.1063/1.3554375, Google ScholarScitation
- 28. W. Melitz, J. Shen, S. Lee, J. S. Lee, A. C. Kummel, R. Droopad, and E. T. Yu, “ Scanning tunneling spectroscopy and Kelvin probe force microscopy investigation of Fermi energy level pinning mechanism on InAs and InGaAs clean surfaces,” J. Appl. Phys. 108, 023711 (2010). https://doi.org/10.1063/1.3462440, Google ScholarScitation
- 29. A. O'Mahony, S. Monaghan, G. Provenzano, I. M. Povey, M. G. Nolan, E. O'Connor, K. Cherkaoui, S. B. Newcomb, F. Crupi, P. K. Hurley, and M. E. Pemble, “ Structural and electrical analysis of the atomic layer deposition of HfO2/n-In0.53Ga0.47As capacitors with and without an Al2O3 interface control layer,” Appl. Phys. Lett. 97, 052904 (2010). https://doi.org/10.1063/1.3473773, Google ScholarScitation
- 30. S. Klejna and S. D. Elliott, “ First-principles modeling of the “clean-up” of native oxides during atomic layer deposition onto III–V substrates,” J. Phys. Chem. C 116(1), 643–654 (2012). https://doi.org/10.1021/jp206566y, Google ScholarCrossref
Please Note: The number of views represents the full text views from December 2016 to date. Article views prior to December 2016 are not included.