Stability of SPSC Under Post-Anodization Treatment

5 Stability of SPSC Under Post-Anodization Treatment 

The behavior of PSC under thermal treatment is of real importance, since during the growth the substrate is exposed to high temperatures. To study this behavior, the annealing experiments at 900-1700 °C were conducted in both Ar atmosphere and in a vacuum in a resistive furnace. 

AES showed that thermal treatment of porous material could result in the change of C/Si ratio as compared with initial stoichiometry. Namely, carbon concentration gradient with the carbon content continuously increasing towards the surface was detected in PSC structures annealed under certain conditions. 

Experimental data on the thermal stability of SPSC can be summarized as follows (i) no essential changes in porous material composition (within AES accuracy), when nanoporous SiC was annealed at temperatures up to 1700 °C in Ar ambient and 1500 °C in a vacuum were found (ii) the composition of microporous SiC annealed in Ar ambient did not change after the treatment at temperatures up to 1500 °C (iii) microporous SiC structures were thermally stable in vacuum within the 900-1200 °C temperature range (iv) PSC surface graphitization occurred in both types of PSC structure after annealing in a vacuum at 1700 °C. 

On this basis, the following conclusions were derived  

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