Paper EM+TF-TuM2
In Situ TMA Pre-Treatment Study of GaAs and In0.53Ga0.47As Surfaces
Tuesday, November 1, 2011, 8:20 am, Room 210
| Session: |
High-k Dielectrics for MOSFETs Part 1 |
| Presenter: |
Barry Brennan, University of Texas at Dallas |
| Authors: |
B. Brennan, University of Texas at Dallas
D.M. Zhernokletov, University of Texas at Dallas
H. Dong, University of Texas at Dallas
R.V. Galatage, University of Texas at Dallas
J. Kim, University of Texas at Dallas
E.M. Vogel, University of Texas at Dallas
R.M. Wallace, University of Texas at Dallas
|
| Correspondent: |
Click to Email |
One of the major issues preventing the integration of high mobility III-V semiconductors into next generation CMOS devices is the formation of high levels of interfacial defects at the high-k/III-V interface. These can have the effect of pinning the Fermi level and preventing optimal operation of the devices. Engineering the interface between these materials therefore becomes of critical importance to try and reduce the defect density. Identification of the individual defects however is not a trivial matter with correlation between electrical data and physical measurement techniques rarely seen. This study aims to investigate the effect of in-situ chemical treatments prior to Al2O3 deposition on (NH4)2S treated GaAs and InGaAs surfaces, in terms of both physical characterization by X-ray photoelectron spectroscopy (XPS) and electrical measurements from MOS capacitors.
The reduction of interfacial oxides through a “clean up” effect by a ligand exchange mechanism with the tri-methyl aluminum (TMA) precursor for atomic layer deposition (ALD) of Al2O3 is well known, [1,2] however little work has been carried out to optimize this process and determine whether variations in the effect are seen as a result of changes in the number of TMA cycles or pulse time prior to oxide deposition. Variations in the presence of arsenic surface features, (i.e. As-As bonding or surface dimers) come under particular focus.The effect of post deposition annealing is also investigated specifically in terms of the potential role hydrogen could play in passivating defects at the interface. [3]
[1] C. L. Hinkle, A. M. Sonnet, E. M. Vogel, S. McDonnell, G. J. Hughes, M. Milojevic, B. Lee, F. S. Aguirre-Tostado, K. J. Choi, H. C. Kim, J. Kim, R. M. Wallace, Appl. Phys. Lett. 92, 071901, (2008)
[2] B. Brennan, M. Milojevic, H.C. Kim H.C, P.K. Hurley, J. Kim, G. Hughes, R.M. Wallace, Electrochem. Solid-State Lett., 12, 6, (2009)
[3] H. D. Trinh, E. Y. Chang, P. W. Wu, Y. Y. Wong, C. T. Chang, Y. F. Hsieh, C. C. Yu, H. Q. Nguyen, Y. C. Lin, K. L. Lin, M. K. Hudait, Appl. Phys. Lett. 97, 042903 (2010)