Comparative study of the role of the nucleation stage on the final crystalline quality of (111) and (100) silicon carbide films deposited on silicon substrates.

Abstract

We study the impact of the nucleation step on the final crystalline quality of 3C-SiC heteroepitaxial films grown on (111) and (100) oriented silicon substrates by low pressure chemical vapor deposition. The evolution of both the structural and morphological properties of 3C-SiC epilayers in dependence on the only nucleation parameters (propane flow rate and duration of the process) are investigated by means of x-ray diffraction, scanning electron, atomic force, and optical microscopies. At first, we show how the formation of interfacial voids is controlled by the experimental parameters, as previously reported, and we correlate the density of voids with the substrate sealing by using an analytical model developed by V. Cimalla et al. [Mater. Sci. Eng., B 46, 190 (1997)]. We show that the nucleation stage produces a more dense buffer layer in case of (111) substrates. Further, we investigate the impact of the nucleation parameters on the crystalline quality of 3C-SiC epilayers. Within our experimental setup, the crystalline quality of (100) oriented 3C-SiC films is more rapidly evolving than (111) films for low propane contents (0.025%–0.05% in hydrogen), whereas a common degradation of the crystalline quality is reported for both cases for the higher propane contents. In parallel, we investigate the morphological features of the epilayers. The (111) oriented epilayers are well coalesced irrespectively of the nucleation condition, contrarily to the (100) films. Finally, for both orientations we report on the dependence of the formation of double positioning domains (twins) on the nucleation conditions. Such defects can be suppressed within (111) films but not within (100) films. We highlight the role of the substrate sealing and discuss in what extent it can be responsible of the observations by reducing the contribution of the silicon outdiffusing and by allowing a more pronounced two-dimensional growth mode for (111) oriented 3C-SiC films.

Structural and electrical characterizations of n-type implanted layers and ohmic contacts on 3C-SiC

“…The 3C-SiC non-intentionally doped (nid) films, used for this study, were hetero-epitaxially grown on (1 0 0) Si wafers of 100 mm diameter by using a horizontal resistively heated hot wall CVD reactor [18]. The growth was performed using silane (SiH 4 ) and propane (C 3 H 8 ) as precursor gases and purified hydrogen (H 2 ) as carrier gas following the classical two stages process defined by Nishino et al [19], without initial surface de-oxidation.…”

A Facile Method for Heteroepitaxial Growth of Homogeneous 3C-SiC Thin Films on Both Surfaces of Suspended Si Wafer by Conventional Chemical Vapor Deposition

“…Interface voids often emerge in the growth of 3C-SiC on Si substrate. 17 This phenomenon is associated with growth process; process temperature, 18 carbonization ramp 19 and experimental parameters 20 are factors to influence the interface void inhibition. When growth is performed at low pressure and high temperature, surface atoms tend to evaporate due to high vapor pressure of silicon.…”

Growth mode and electric properties of graphene and graphitic phase grown by argon–propane assisted CVD on 3C–SiC/Si and 6H–SiC

“…3C-SiC epilayers were grown on silicon substrates by using the two step deposition process initially introduced by Nishino et al [21] and adapted to our own CVD reactor in terms of temperatures, precursors dilution ratios and process duration (see [22] for further details). For this work, the 3C-SiC epilayers were grown on on axis Si(100) and Si(111) highly resistive substrates (r Si 410,000 O cm).…”