Temperature-dependent photoluminescence properties of porous fluorescent SiC

Abstract

A comprehensive study of surface passivation effect on porous fluorescent silicon carbide (SiC) was carried out to elucidate the luminescence properties by temperature dependent photoluminescence (PL) measurement. The porous structures were prepared using an anodic oxidation etching method and passivated by atomic layer deposited (ALD) Al2O3 films. An impressive enhancement of PL intensity was observed in porous SiC with ALD Al2O3, especially at low temperatures. At temperatures below 150 K, two prominent PL emission peaks located at 517 nm and 650 nm were observed. The broad emission peak at 517 nm was attributed to originate from the surface states in the porous structures, which was supported by X-ray photoelectron spectra characterization. The emission peak at 650 nm is due to donor-acceptor-pairs (DAP) recombination via nitrogen donors and boron-related double D-centers in fluorescent SiC substrates. The results of the present work suggest that the ALD Al2O3 films can effectively suppress the non-radiative recombination for the porous structures on fluorescent SiC. In addition, we provide the evidence based on the low-temperature time-resolved PL that the mechanism behind the PL emission in porous structures is mainly related to the transitions via surface states.

Strong visible-light emission in annealed poly(acrylic acid)

“…Deposition of PAA on porous SiC surface improves the mechanical adhesion. The porous layer is fabricated by an anodic oxidation process [24,25]. The PL emission from the PAA on a porous SiC is shown in Fig.…”

Voltage-Controlled Anodic Oxidation of Porous Fluorescent SiC for Effective Surface Passivation

“…Moreover, porous structures fabricated in fluorescent SiC can emit simultaneous blue–green light, which is attributed to surface-defects-related emissions [ 12 , 13 , 14 ]. Passivation by atomic layer-deposited (ALD) dielectric films dramatically increased the emission intensity of the porous fluorescent SiC layer [ 15 , 16 ]. Therefore, it is expected that combining the yellow–orange emission from fluorescent SiC with the blue–green light in the porous structures will result in the emission of white light with a high color-rendering index [ 5 , 17 ].…”

Structure and optical properties of porous SiC film grown by magnetron sputtering on porous anodic aluminium oxide template

“…The enhanced luminescence of porous 6H-SiC compared to bulk 6H-SiC were observed at both 5 K and 300 K temperature [9]. Lu et al [10,11] prepared N-B co-doped 6H-SiC with 10 µm porous surface structure by anodic oxidation method. After passivation with 20 nm thick Al 2 O 3 , the PL intensity from the porous layer was significantly enhanced by a factor of more than 1225 [10,11].…”

“…Lu et al [10,11] prepared N-B co-doped 6H-SiC with 10 µm porous surface structure by anodic oxidation method. After passivation with 20 nm thick Al 2 O 3 , the PL intensity from the porous layer was significantly enhanced by a factor of more than 1225 [10,11]. Fluorescent SiC with porous surface can be used for high performance and rare-earth element free white light emitting applications [10,11].…”

“…After passivation with 20 nm thick Al 2 O 3 , the PL intensity from the porous layer was significantly enhanced by a factor of more than 1225 [10,11]. Fluorescent SiC with porous surface can be used for high performance and rare-earth element free white light emitting applications [10,11]. Li et al [12,13] used two-dimensional (2D) porous structure to improve PL property of SiC.…”