This paper reports the feasibility of synthesis and characterization of One Dimensional nano scale Porous Silicon Photonic Crystals (1D-PSPC) prepared using electrochemical anodization of p-type crystalline silicon wafer by adjusting the current densities. Two structures PSPC1 and PSPC2 with current density 25 and 35mA/cm with 10 minutes of etching time were prepared. Structural and optical pro...

Macroporous silicon has been etched from n-type Si, using a vertical etching cell where no rear side contact on the silicon wafer is necessary. The resulting macropores have been characterised by means of Scanning Electron Microscopy (SEM). After etching, SiO2 was thermally grown on the top of the porous silicon as an insulating layer and Si3N4 was deposited by means of Low Pressure Chemical Va...

Isotropic etching of silicon in HF-based solutions is expected to be controlled by the diffusion of fluoride to the silicon surface. In order to gain quantitative understanding of the process, we studied etching of silicon in HF/HNO3/H2O via circular mask openings and compared the results with the theoretical expectations. The cavity edges due to etching under the mask were analyzed with a high...

14 The development and status of what is commonly called the Gerischer mechanism of silicon etching in 15 fluoride solutions is reviewed. The two most widely used and studied wet etchants of silicon are F 16 and OH . Their mechanisms of atom removal share many things in common; in particular, chemical pas17 sivation by a hydrogen-terminated surface plays an important role in both. Crucially, ho...

High quality graphene films can be fabricated by chemical vapor deposition (CVD) using Ni and Cu as catalytic substrates. Such a synthesis procedure always requires a subsequent transfer process to be performed in order to eliminate the metallic substrate and transfer the graphene onto the desired surface. We show here that such a transfer process causes significant contamination of the graphen...

We report the effect of chemical etching of p-GaN using molten KOH:NaOH solution on leakage currents, light output power, and electrostatic discharge ESD characteristics of GaN light-emitting diodes LEDs . Photoluminescence and capacitance–voltage measurement indicated that a deep donor–acceptor pair DDAP was densely concentrated near the p-GaN surface region 18 nm and the defects were effectiv...

: Analysis methods for electrochemical etching baths consisting of various concentrations of hydrofluoric acid (HF) and an additional organic surface wetting agent are presented. These electrolytes are used for the formation of meso- and macroporous silicon. Monitoring the etching bath composition requires at least one method each for the determination of the HF concentration and the organic co...

In this paper, we study the electrochemical anodization of n-type heavily doped 4 H-SiC wafers in a HF-based electrolyte without any UV light assistance. We present, in particular, the differences observed between the etching of Si and C faces. In the case of the Si face, the resulting material is mesoporous (diameters in the range of 5 to 50 nm) with an increase of the 'chevron shaped' pore de...