AVS 50th International Symposium
    Electronic Materials and Devices Wednesday Sessions
       Session EM-WeA

Paper EM-WeA7
Macroscopic and Microscopic Electronic Behavior of Cubic Inclusions in 4H-SiC

Wednesday, November 5, 2003, 4:00 pm, Room 321/322

Session: Diamond/Contacts to SiC
Presenter: K.-B. Park, The Ohio State University
Authors: K.-B. Park, The Ohio State University
Y. Ding, The Ohio State University
J.P. Pelz, The Ohio State University
K.C. Palle, Arizona State University
M.K. Mikhov, Arizona State University
B.J. Skromme, Arizona State University
A. Los, Mississippi State University
M.S. Mazzola, Mississippi State University
Correspondent: Click to Email
Double-stacking-fault cubic inclusions in n-type 4H-SiC@footnote 1@ were studied with ballistic electron emission microscopy (BEEM) in ultra high vacuum where the inclusions intersect a Pt/SiC Schottky barrier (SB) interface. We confirmed prior proposals@footnote 2@ that the inclusions behave as quantum wells, and found a propagating two-dimensional quantum well conduction band minimum (CBM) at ~0.53 eV below the CBM of the bulk 4H-SiC host. This agrees well with calculations of the quantum well state@footnote 3@ and is close to the SB height lowering found with macroscopic I-V and C-V measurements.@footnote 4@ The macroscopic C-V SB heights were found to be quite similar to macroscopic I-V measurements, which is interesting because less than 5% of the Pt/SiC interface is on the low-barrier-height inclusions. We believe this similarity between C-V, I-V, and BEEM measurements can be explained by the actual SBH of the inclusions at the Pt/SiC interface, along with changing occupation of the quantum well states away from the interface during C-V measurements. We are currently developing electrostatic modeling to quantify this hypothesis. We will also discuss the first "hole BEEM" measurements of SiC on a Pt/p-type 4H-SiC (presently without inclusions) SB interface. We found a 1.40 eV p-type SB height, compared with 1.54 eV of Pt on n-type 4H-SiC, as well as a double threshold, suggesting a possible second valance band maximum. @FootnoteText@@footnote 1@R. S. Okojie, M. Zhang, P. Pirouz, S. Tumakha, G. Jessen, and L. J. Brillson, Appl. Phys. Lett. 79, 3056 (2001).@footnote 2@T. A. Kuhr, J. Q. Liu, H. J. Chung, M. Skowronski, and F. Szmulowicz, J. Appl. Phys. 92, 5863 (2002).@footnote 3@H. Iwata, U. Lindefelt, S. Oberg, and P. Briddon, J. Phys. C 14, 12733 (2002).@footnote 4@B. J. Skromme, K. Palle, C. D. Poweleit, L. R. Bryant, W. M. Vetter, M. Dudley, K. Moore, and T. Gehoski, Mater. Sci. Forum 389-393, 455 (2002).