White-light emissions from p-type porous silicon layers by high-temperature thermal annealing

Abstract

In this study, the white-light emissions, including red, green and blue colors, appearing on the same porous silicon samples are originally introduced by a thermal-annealing method. The SEM, FTIR, and PL are discussed for different annealing temperature cases. The FTIR is used to monitor the chemical bonding structures of the PS samples under different annealing temperatures. The results show that the variation of chemical bonding relates to the variation of the emission wavelength. The emission intensities of the blue-green-light components are enhanced with the increase of annealing temperature. The PL spectra cover the entire visible region under the excitations of He-Cd laser beam, and a strong white-light emission can be observed by the naked eye at room temperature.

Fabrication of Silicon Carbide from Recycled Silicon Wafer Cutting Sludge and Its Purification

“…The Si sludge shows peaks at 618 cm −1 ,1065 cm −1 , 800 cm −1 , 1134 cm −1 , 1225 cm −1 , and 2124 cm −1 , which belong to Si-O-Si, Si-O, Si-O-C, Si-Si, and C≡C bonds, respectively. This analysis showed similarities with other analyses indicating that the Si sludge contains a little amount of C and O. SiC synthesized at the optimum condition showed peaks at 760 cm −1 , 1047 cm −1 , and 2110 cm −1 , corresponding to Si-O, Si-O-C, and C≡C bonds [29][30][31][32][33]. Both Si sludge and synthesized SiC contain carbon in the samples with trace amounts of oxide.…”

Optical properties of photo-electrochemical etching of anisotropic silicon (110)

“…The increases of the PL intensity as a function . Tsai et al believed that more Si-H bonds is also the main reason of the increase of the PL intensity [13]. Besides that, the increases of the PL intensity are attributed to the larger surface area as compared to unetched Si samples.…”

Photoluminescence enhancement of Si nanocrystals embedded in SiO2 by thermal annealing in air

“…The fine microstructure of the Si-NCs reveals a regular lattice structure consistent with single crystal phase of Si. The crystal size distribution obtained from the HRTEM examination is shown as a histogram in [7,[27][28][29]. For the as-deposited sample, the R mode shows a broad absorption band with its maximum around 440 cm −1 , the B mode appears as a small absorption peaking at ∼815 cm −1 , whereas the overlap of the absorptions corresponding to the AS1 and AS2 modes results in a broad band ranging from 920 to 1270 cm −1 .…”