Interfacial differences between SiO2 grown on 6H-SiC and on Si(100)

Abstract

Oxides grown on p-type 6H-SiC and on Si(100) were studied using x-ray photoelectron spectroscopy and sputter depth profiling to determine what differences exist between the two systems. The oxide on SiC is found to be stoichiometric SiO2, but the oxide is structurally different from the oxide grown on Si(100). We propose that strain introduced during processing accounts for the structural differences. We also found that Si atoms at the SiO2/SiC interface are chemically different from Si atoms in the bulk of SiC and a number of possible explanations for this are given.

Effect of oxidation and reoxidation on the oxide-substrate interface of 4H- and 6H-SiC

“…4,5 We recently reported on interfacial differences in the thermal oxides grown on Si͑100͒ and on 6H-SiC using sputter depth profiling ͑SDP͒ and x-ray photoelectron spectroscopy ͑XPS͒. 6 In this work, we compare oxides grown on 4H-and 6H-SiC. By probing the different oxide-carbide interfaces, we can discover why the interface trap densities and the channel mobilities are different between 4H and 6H and why the mobilities are less than their predicted values.…”

“…The experimental conditions for SDP, using Ar ions ͑2 keV͒, and XPS, using Mg x rays ͑1253.6 eV͒, have been previously reported. 6 The peak area and the binding energy ͑BE͒ of the Si 2p, O 1s, and C 1s XPS photoelectrons were measured. The binding energies have been referenced to the C 1s peak of the SiC substrate at 282.7 eV which was found to remain constant for both 4H and 6H samples during SDP.…”

Bias-stress induced threshold voltage and drain current instability in 4H–SiC DMOSFETs

“…Though, SiC DMOSFETs are beginning to be commercialized [4], there are still a number of issues that need to be solved to improve the performance of SiC DMOSFETs. The issues, attributed to the high density of SiC/SiO 2 interface traps and near-interface traps [5,6], are a negative threshold voltage (normally-on) [7][8][9], a low inversion-channel carrier mobility [10], reliability issues [11][12][13], and threshold-voltage instability [14,15].…”

Al2O3/SiO2 films prepared by electron-beam evaporation as UV antireflection coatings on 4H-SiC

“…Second, the layer was adhered by oxygen and steam when exposed in the air. The width of the transition from SiO 2 to SiC is due to the escape depth of the photoelectrons as well as Al 2 O 3 to SiO 2 , and the interfaces may be abrupt actually [12].…”