Properties of bulk SiC and SiC structures

 

 

- SiC Parameters

- Cleavage planes in SiC wafers

- Colours of silicon carbide

- Electron mobility in 4H, 6H, and 3C SiC

- Etching of silicon carbide in molted KOH

- SiO2-SiC interface - can we make it as good as the Si–SiO2 interface?

 

 

 

SiC parameters database in electronic archive "New Semiconductor Materials. Characteristics and Properties" at  Ioffe Institute. This is the most comprehensive, continuously updated online database initially based on  [Properties of Advanced Semiconductor Materials : GaN, AlN, InN, BN, SiC, SiGe", Editors: M. E. Levinshtein, S.L. Rumyantsev, and M.S. Shur (John Wiley & Sons, Inc.,  2001) ISBN 0-471-35827-4.]. 

 

Cleavage planes in SiC wafers:

The preferred cleavage planes are the (11-20) and (1-100)  planes, and the latter cleavage plane is more reproducible to make. [M. Syvajarvi, R. Yakimova, E. Janzen, Cross-sectional cleavages of SiC for evaluation of epitaxial layers, Journal of Crystal Growth, 208, (2000), 409-415]

   Note, that all Cree wafers have the primary flat parallel to {10-10} plane. So, if you wish to cut the whole Cree wafer in two peaces, do the first cleavage parallel to the primary flat.

 

SiC colours:

Black

6H   SiC  

high Al doped

Purple

24H SiC  

N-doped

Blue

6H   SiC  

Al doped

Green

6H   SiC  

N doped

Yellow Green

3C   SiC  

N doped

Yellow

3C   SiC  

undoped

Yellow Orange

8H   SiC  

N doped

Red

27H SiC  

N doped

Light Brown

4H   SiC  

low N doped

 

Electron Mobility in 4H, 6H, and 3C SiC

Quite complete summary of experimental and MC data for the mobility measured perpendicular to the c-axis (in 4H and 6H), fitted with empirical formulas depending on doping, temperature and field (less than 106 V/cm). [Electron Mobility Models for 4H, 6H, and 3C SiC, M. Roschke, F. Schwierz, IEEE tr ED,48,1442, (2001)]

 

SiC Etching in Molted KOH:

Use molten KOH at 480C; container -  nickel crucible; after the KOH becomes  molten - wait for 1 h prior to etching; an ambiance - the air. Polishing etching is observed on C-face SiC, while Si-face become lustreless due to defects decoration. Etch rate of C-face is much higher than etch rate of Si-face. [M. Syvajarvi, R. Yakimova, E. Janzen, Cross-sectional cleavages of SiC for evaluation of epitaxial layers, Journal of Crystal Growth, 208, (2000), 409-415]

 

Can we make the SiC–SiO2 interface as good as the Si–SiO2 interface?

No, we cannot... [Massimiliano Di Ventra, APL, 79  (2001) pp. 2402-2404]