Considerably long carrier lifetimes in high-quality 3C-SiC(111)

Abstract

As a challenge and consequence due to its metastable nature, cubic silicon carbide (3C-SiC) has only shown inferior material quality compared with the established hexagonal polytypes. We report on growth of 3C-SiC(111) having a state of the art semiconductor quality in the SiC polytype family. The x-ray diffraction and low temperature photoluminescence measurements show that the cubic structure can indeed reach a very high crystal quality. As an ultimate device property, this material demonstrates a measured carrier lifetime of 8.2 mu s which is comparable with the best carrier lifetime in 4 H-SiC layers. In a 760-mu m thick layer, we show that the interface recombination can be neglected since almost all excess carriers recombines before reaching the interface while the surface recombination significantly reduces the carrier lifetime. In fact, a comparison of experimental lifetimes with numerical simulations indicates that the real bulk lifetime in such high quality 3C-SiC is in the range of 10-15 mu s

Laser Power Converter Architectures Based on 3C‐SiC with Efficiencies >80%

“…[ 34 ] Although carrier lifetimes in SiC heavily depend on the crystal growth conditions, under low injection levels, lifetimes of up to 15 μs in 3C‐SiC bulk are reported in the literature. [ 31 ] At low illumination levels, SRH dominates the recombinations because there are a large number of traps available. However, an increase in the input power density leads to higher SRH lifetimes due to a lower percentage of vacant traps compared to the excess carrier concentration.…”

“…[ 29 ] SiC is found in several polytypes, being the hexagonal 4H and 6H the most employed so far. [ 30 ] Efforts are being made to obtain high‐quality cubic 3C crystals because of the high electron mobility and isotropic properties, [ 31 ] and the fact that 3C can be grown on large commercially available Si wafers, notably reducing fabrication costs. [ 32 ] SiC has not been considered for solar PV applications due to its high energy gap and poor solar spectrum absorption.…”

Efficiency analysis and electronic structures of 3C-SiC and 6H-SiC with 3d elements impurities as intermediate band photovoltaics

“…There are no natural materials for stacking with silicon. Sun et al 15 from Linköping University Electronic Press produced high-quality 3C-SiC with considerably long carrier lifetimes. However, in this type of solar cells, critical parameters such as dot spacing and size, as well as fluctuations in the sizes of dots, must be controlled for tuning the absorption spectrum of each cell.…”

“…This problem can be solved by quantum dot-based structures. 15 The bond between the Si atom and the C atom is strong, with energy equal to 6.34 eV (this is 4.63 eV between two silicon atoms). 4 The geometry of the nanoparticle arrays also needs to be optimized to enhance carrier transport through resonant hopping between layers in a cell.…”

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

“…WZ polytype such as 4H-SiC has a wider bandgap than ZB polytype such as 3C-SiC, which makes WZ polytypes more suitable for high power electronics than ZB polytypes. [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.…”