IN SITU ETCHING TREATMENTS OF EPITAXIAL LAYER BY USING DIFFERENT GAS COMPOSITION FOR MORPHOLOGICAL QUALITY IMPROVEMENT OF THE SURFACES.

Sonia De Angelis 1,2,4LUCIANO SCALTRITO 1,4SERGIO FERRERO 1,4DENNIS PERRONE 1,4FABRIZIO PIRRI 1,4MARCO MAUCERI 2STEFANO LEONE 2GIUSEPPE PISTONE 2GIUSEPPE ABBONDANZA 2DANILO CRIPPA 3

1. Dipartimento di Fisica, Politecnico di Torino, corso Duca degli Abruzzi, 24, Torino 10129, Italy
2. ETC srl, Z.I. Pantano D’Arci, Catania 95030, Italy
3. LPE SPA, VIA FALZAREGO,8, MILANO 20021, Italy
4. Material and Microsystems Laboratori-χ Lab, Palazzo “L.EINAUDI”, Lungo Piazza d’Armi, Chivasso, Italy

Abstract

Different homo epitaxial 4H-SiC commercial wafers were investigated after in-situ etching process in an Hot Wall Chemical Vapor Deposition (HWCVD) reactor. We have studied the effects of physical desorption due to different type and mixture of gases at the same process conditions in order to point out the morphology and the structural variations of epitaxial surfaces. As a result to select proper etching treatments.

An optical microscopy inspection was made to trace out a map of defect areas before and after etching treatments. We have analyzed the morphological evolution of the surface in every etching process step by means of marked area on the defect map. We also achived some other important information, concerning structural and morphological changing, by performing Atomic Force Microscopy and Micro Raman spectroscopy analysis on the same defect marked area.

The etched epi-layers showed a significant reduction of defects density and a good surface morphology, various gas treatments induced different variations in the morphological composition of the surface, above all in defect structure. We have tried to correlate morphological and structural changing as well as we used different gases type and mixture composition to perform etching treatments, therefore interesting results were found.

 

Presentation: oral at E-MRS Fall Meeting 2005, Symposium F, by Sonia De Angelis
See On-line Journal of E-MRS Fall Meeting 2005

Submitted: 2005-05-17 06:41
Revised:   2009-06-07 00:44