Optical investigation methods for SiC device development: application to stacking faults diagnostic in active epitaxial layers

Abstract

We present a review of the different optical techniques that can be used to investigate the presence of as-grown and/or process-induced stacking faults (SFs) in 4H–SiC epitaxial layers. A SF is always a finite admixture of different polytypes, and we begin with a brief review of the systematic of SiC polytype structure and electronic properties. Next, we discuss the optical signature and compare with the results of several model calculations, taking successively into account the effect of valence band offset, internal polarization and non-homogeneity of the potential well. Finally, we consider cathodo-luminescence and micro-photoluminescence techniques and show that, in both cases, some screening of the built-in electric field can be achieved.

Damage profile and ion distribution of slow heavy ions in compounds

“…52,53 As the damage level increases with the ion fluence, the stopping power along channeling directions quickly approaches the random stopping power. The small shift of damage profile of ϳ5% resulting from relatively lower stopping power of channeled He ions has been observed in slightly damaged SrTiO 3 . 54 Since this study mainly focuses on heavily damaged SiC samples, such channeling effects on the He stopping power will be ignored.…”

“…The irradiation conditions and experimental results are summarized in Table I. For each of the irradiation conditions, the damage profile in dpa and Au distribution are determined using SRIM 2008.01 full-cascade simulations 34 under the assumptions of a sample density of 3.21 g / cm 3 and threshold displacement energies of 35 and 20 eV for Si and C, respectively. 47 The SRIMpredicted damage profiles are overlaid on top of the corresponding TEM micrographs in Fig.…”

“…In general, the Au profile predicted by SRIM is ϳ30% shallower than that measured by SIMS. One may note that the SRIM prediction is based on the assumptions of a sample density of 3.21 g / cm 3 , and it is well known that, depending on the damage level, irradiation leads to volume expansion up to 10%-20% in the fully amorphous state. 27,45,48,49 However, the volume swelling itself cannot account for ϳ30% deviations.…”

“…Over the years, research and development [1][2][3][4][5][6][7][8] have been devoted to fully utilizing this functional material for high-power, highfrequency, and high-temperature applications, as well as for operation in harsh environments, such as nuclear reactors, high-energy physics experiments, and space applications. SiC materials and composites are being considered for advanced nuclear applications, such as structural materials and fuel coatings in fission reactors and structural components in fusion reactors.…”

Recent Developments on Silicon Carbide Thin Films for Piezoresistive Sensors Applications

“…Currently there are 6H-SiC, 4H-SiC and 3C-SiC wafers commercially available. However, these wafers are still very expensive (Hobgood et al, 2004;Camassel & Juillaguet, 2007), so encouraging studies on crystalline and amorphous SiC films deposited on silicon or SOI (Silicon-On-Insulator) substrates using appropriate techniques. The use of SiC films besides being less expensive has another advantage which is the well known processing techniques for silicon micromachining.…”