Heteroepitaxial 3C-SiC on Si with Various Carbonization Process Conditions

Abstract

The surface morphology and crystallinity of cubic silicon carbide (3C-SiC) films are the most important factors to affect performance of 3C-SiC-based electronic devices. This article presents the effect of carbonization condition, such as the process temperature and the source gas flow rate, on the surface roughness and crystalline quality of heteroepitaxial 3C-SiC films grown on Si (001) substrates. Morphological analysis using scanning electron microscopy (SEM), optical microscopy, and atomic force microscopy (AFM) reveals that decreasing the carbon-based precursor gas-on temperature from 1100°C to 700°C after in situ cleaning significantly improves the surface morphology of subsequent 3C-SiC films. Also, decreasing the carbonization temperature from 1250°C to 1150°C reduces the protrusion defect density from >400/mm 2 to <30/mm 2 . Comparison of crystalline quality of 3C-SiC with two different propane gas flow rates of 3 sccm and 15 sccm during carbonization, using x-ray diffractometry and scanning probe microscopy, indicates little influence on crystalline quality as flow rate changes.

Optimization of growth parameters for growth of high quality heteroepitaxial 3C–SiC films at 1200°C

“…This reduction in temperature is beneficial for layers grown on large area substrates, which are not discussed here. The crystalline quality of the layers can compete with layers grown at much higher temperatures of up to 1380°C [8,19,23,24], which was confirmed by XRD-and Raman-measurements. A high C/Si-ratio, a low off-oriented substrate and a high layer thickness are required for the growth of high quality layers.…”

Surface saturation control on the formation of wurtzite polytypes in zinc blende SiC nanofilms grown on Si-(100) substrates

“…[4] WZ polytypes are thought to be unfavourable thermodynamic stable phases at a temperature lower than 1500 K, while ZB polytypes are the most thermodynamic stable phases in common sense. [5] To date, WZ SiC films can be homoepitaxially grown on commercial available wafers at a temperature higher than 1630 K, [6,7] while ZB SiC films can be relatively easily heteroepitaxially grown on Si wafers in a wide range from 1250 K to 1600 K. [8] ZB monocrystalline hetero-growth on Si substrate has been deeply investigated for decades. [9][10][11][12] Various studies have been carried out to improve the monocrystalline quality, [9] reduce the growth temperature, [10,11] and increase the wafer sizes.…”