Kerf-Less Exfoliated Thin Silicon Wafer Prepared by Nickel Electrodeposition for Solar Cells.

Ultra-thin and large-area silicon wafers with a thickness in the range of 20-70 μm, were produced by spalling using a nickel stressor layer. A new equation for predicting the thickness of the spalled silicon was derived from the Suo-Hutchinson mechanical model and the kinking mechanism. To confirm the reliability of the new equation, the proportional factor of stress induced by the nickel on the silicon wafer, was calculated.

Ultrasensitive detection of low-ppm HS gases based on palladium-doped porous silicon sensors.

In this study, the sensing properties of palladium-doped porous silicon (Pd/p-Si) substrates for low-ppm level detection of toxic HS gas are investigated. A Si substrate with dead-end pores ranging from nano- to macroscale was generated by a combined process of metal-assisted chemical etching (MacE) and electrochemical etching with tuned reaction time, in which nano-Pd catalysts were decorated by E-beam sputtering deposition. The sensing properties of the Pd/p-Si were enhanced as the thickness of the substrate layer increased; along with the resulting variation in surface area, this resulted in superior HS sensing performances in the low-ppm range (less than 3 ppm), with a detection limit of 300 ppb (sensitivity 30%) at room temperature.

Room-Temperature H₂ Gas Sensing Characterization of Graphene-Doped Porous Silicon via a Facile Solution Dropping Method.

In this study, a graphene-doped porous silicon (G-doped/p-Si) substrate for low ppm H₂ gas detection by an inexpensive synthesis route was proposed as a potential noble graphene-based gas sensor material, and to understand the sensing mechanism. The G-doped/p-Si gas sensor was synthesized by a simple capillary force-assisted solution dropping method on p-Si substrates, whose porosity was generated through an electrochemical etching process. G-doped/p-Si was fabricated with various graphene concentrations and exploited as a H₂ sensor that was operated at room temperature.

Surface oxidation behaviors of Cd-rich CdSe quantum dot phosphors at high temperature.

The optical properties of quantum dots (QDs) are altered by exposure to air and light; upon such exposure, the quantum yield is typically reduced. Improved understanding of surface oxidation and oxide-layer behavior, both of which influence the photoluminescence of QDs, is necessary for advancing the use of QDs. In this study, the oxide layer properties of QDs are investigated.

Improvement of dispersion stability and optical properties of CdSe/ZnSe structured quantum dots by polymer coating.

In this study, CdSe core and CdSe/ZnSe core/shell quantum dots with a narrow size distribution were synthesized in a micro-reactor. A PMMA coating applied to the surface of CdSe/ZnSe core/shell QDs to prevent degradation gave improved dispersion stability compared to the CdSe core and CdSe/ZnSe core/shell. Many previous approaches to dispersion stability have not been quantitatively assessed.