scholarly journals Comparative Study on Electronic, Emission, Spontaneous Property of Porous Silicon in Different Solvents

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
M. Naziruddin Khan ◽  
M. A. Majeed Khan ◽  
A. S. Al Dwayyan ◽  
J. Puzon Labis
Keyword(s):  
Porous Silicon ◽  
Silicon Wafer ◽  
Wafer Surface ◽  
Etching Technique ◽  
Solvent Influence ◽  
Cross Section Area ◽  
Section Area ◽  
Simple Chemical ◽  
Crystalline Nature ◽  
Si Wafer

Luminescent porous silicon (Psi) fabricated by simple chemical etching technique in different organic solvents was studied. By quantifying the silicon wafer piece, optical properties of the Psi in solutions were investigated. Observation shows that no photoluminescence light of Psi in all solvents is emitted. Morphology of Psi in different solvents indicates that the structure and distribution of Psi are differently observed. Particles are uniformly dispersive with the sizes around more or less 5–8 nm. The crystallographic plane and high crystalline nature of Psi is observed by selected area diffraction (SED) and XRD. Electronic properties of Psi in solutions are influenced due to the variation of quantity of wafer and nature of solvent. Influence in band gaps of Psi calculated by Tauc’s method is obtained due to change of absorption edge of Psi in solvents. PL intensities are observed to be depending on quantity of silicon wafer, etched cross-section area on wafer surface. Effects on emission peaks and bands of Psi under temperature annealing are observed. The spontaneous signals of Psi measured under high power Pico second laser 355 nm source are significant, influenced by the nature of solvent, pumped energy, and quantity of Si wafer piece used in etching process.

scholarly journals Growth and Self-Assembly of Silicon–Silicon Carbide Nanoparticles into Hybrid Worm-Like Nanostructures at the Silicon Wafer Surface

Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 954 ◽  
Author(s):  
Manuel Perez-Guzman ◽  
Rebeca Ortega-Amaya ◽  
Yasuhiro Matsumoto ◽  
Andres Espinoza-Rivas ◽  
Juan Morales-Corona ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Silicon Wafer ◽  
Self Assembly ◽  
Silicon Nanoparticles ◽  
Hybrid Nanostructures ◽  
Wafer Surface ◽  
Silicon Carbide Nanoparticles ◽  
Silicon Based ◽  
Silicon Silicon ◽  
Si Wafer

This work describes the growth of silicon–silicon carbide nanoparticles (Si–SiC) and their self-assembly into worm-like 1D hybrid nanostructures at the interface of graphene oxide/silicon wafer (GO/Si) under Ar atmosphere at 1000 °C. Depending on GO film thickness, spread silicon nanoparticles apparently develop on GO layers, or GO-embedded Si–SiC nanoparticles self-assembled into some-micrometers-long worm-like nanowires. It was found that the nanoarrays show that carbon–silicon-based nanowires (CSNW) are standing on the Si wafer. It was assumed that Si nanoparticles originated from melted Si at the Si wafer surface and GO-induced nucleation. Additionally, a mechanism for the formation of CSNW is proposed.

Study of Chelating Agents in Silicon Wafer Polishing Slurry

2012 ◽  
Vol 581-582 ◽  
pp. 790-793
Author(s):  
Xi Hui Zhang ◽  
Gui Xiang Wang
Keyword(s):  
Silicon Wafer ◽  
Chelating Agents ◽  
Chelating Agent ◽  
Wafer Surface ◽  
Contamination Level ◽  
Copper Contamination ◽  
Wafer Polishing ◽  
Si Wafer

Several chelating agents in silicon polishing slurries were studied about their effects on copper adhesion to the surface of silicon wafer. The copper contamination level on the Si wafer surface was measured with GFAAS. The results indicate that PAA and HEDP for acid slurries can reduce 80% copper contamination with respect to the situation of without chelating agent. EDTA, the most common chelating agent for alkaline slurries, has no predominant compared with FA/O and AEEA. The copper contamination on Si wafer surface can reduce nearly 50% by adding EDTA while the addition of FA/O or AEEA in the same concentration for alkaline slurries can reach more than 70% reduction of copper contamination level.

The Effect of Etchant Concentration and Temperature on Surface Finish of Silicon Wafer Thinning

2015 ◽  
Vol 1115 ◽  
pp. 29-32
Author(s):  
M.A. Safaruddin ◽  
S.F.M. Shahar ◽  
I.H. Jaafar
Keyword(s):  
Surface Roughness ◽  
Silicon Wafer ◽  
Potassium Hydroxide ◽  
Ion Beam ◽  
Wafer Surface ◽  
Wet Chemical ◽  
Wet Chemical Etching ◽  
Focus Ion Beam ◽  
Wafer Thinning ◽  
Si Wafer

Fabrication of silicon (Si) wafer microfilters via focus ion beam (FIB) sputtering (milling/drilling) is planned. However, due to limitations of FIB sputtering, the wafer has to be initially thinned to a certain thickness to ensure that micron-scale through holes can be successfully manufactured. This paper reports on thinning of a silicon wafer via wet chemical etching using 15, 20, and 25% w/w potassium hydroxide (KOH) at 3 different etchant temperatures (80oC, 90oC, and 100oC). The target is to achieve 100 μm with the lowest time taken and wafer surface roughness after etching. From the experiments conducted, it was determined that KOH solution at 15% w/w concentration at 100oC produced the best result with an etch rate of 5.43 μm/min, surface roughness (Ra) of 0.12μm and thickness of 123.00μm.

EFFECT OF BEDLOAD SEDIMENT NATURAL COMPOSITION ON GEOMETRIC AND DINAMIC CHARACTERISTICS OF CHANNEL FORMS

2018 ◽  
pp. 36-39
Author(s):  
N Ikramov ◽  
T Majidov
Keyword(s):  
Research Work ◽  
Laboratory Data ◽  
Hydroelectric Station ◽  
Negative Consequences ◽  
Movement Velocity ◽  
Reservoir Volume ◽  
Pump Station ◽  
Cross Section Area ◽  
Section Area ◽  
Bedload Sediment

The article brings up data on sediment diversity at watercourse bed and on their movement in the form of ridges. The ridge form movement of sediment leads to the reduction of reservoir volume and canal cross section area, which has an effect on their carrying capacity, filling of pump station forechambers and hydroelectric station pressure basins with sediment. The presence of sediment in flow leads to abrasive deterioration of pumps, water motors and pressure pipes and to other negative consequences. Research work tasks on the study of these effects have been examined with the purpose of preventing such negative consequences. On the basis of laboratory data diagrams and relationships were obtained for ridge length, height and movement velocity vs. sediment hydraulic and geometric sizes.

Modeling and Analyzing on Nonuniformity of Material Removal in Chemical Mechanical Polishing of Silicon Wafer

2004 ◽  
Vol 471-472 ◽  
pp. 26-31 ◽  
Author(s):  
Jian Xiu Su ◽  
Dong Ming Guo ◽  
Ren Ke Kang ◽  
Zhu Ji Jin ◽  
X.J. Li ◽  
...  
Keyword(s):  
Silicon Wafer ◽  
Chemical Mechanical Polishing ◽  
Material Removal ◽  
Mechanical Polishing ◽  
Wafer Surface ◽  
Removal Mechanism ◽  
Particle Movement ◽  
Material Removal Mechanism ◽  
The Relationship ◽  
Nonuniform Material

Chemical mechanical polishing (CMP) has already become a mainstream technology in global planarization of wafer, but the mechanism of nonuniform material removal has not been revealed. In this paper, the calculation of particle movement tracks on wafer surface was conducted by the motion relationship between the wafer and the polishing pad on a large-sized single head CMP machine. Based on the distribution of particle tracks on wafer surface, the model for the within-wafer-nonuniformity (WIWNU) of material removal was put forward. By the calculation and analysis, the relationship between the motion variables of the CMP machine and the WIWNU of material removal on wafer surface had been derived. This model can be used not only for predicting the WIWNU, but also for providing theoretical guide to the design of CMP equipment, selecting the motion variables of CMP and further understanding the material removal mechanism in wafer CMP.

scholarly journals Long-term evaluation of rootstock effects on cropping and tree parameters of selected sweet cherry cultivars

2020 ◽  
Vol 47 (No. 1) ◽  
pp. 13-20
Author(s):  
Jitka Blažková ◽  
František Paprštein ◽  
Lubor Zelený ◽  
Adéla Skřivanová ◽  
Pavol Suran
Keyword(s):  
Sweet Cherry ◽  
Cross Section Area ◽  
Section Area ◽  
Natural Tendency ◽  
Term Evaluation ◽  
The Mean ◽  
Sweet Cherry Cultivars ◽  
Tree Characteristics ◽  
Gisela 5

The cropping of six sweet cherry cultivars that originated in the Research and Breeding Institute of Pomology at Holovousy, and a standard one, ‘Burlat’, were evaluated on three rootstocks in the period of 2007–2017. Trees planted in a spacing of 1.5 m × 5.0 m were trained as tall spindle axes utilising their natural tendency to develop a central leader. On the standard rootstock, P-TU-2, ‘Tim’ was the most productive with a mean total harvest of 47.6 kg per tree. ‘Sandra’ yielded the most on the PHLC rootstock with 56.2 kg per tree and ‘Helga’ yielded the most on Gisela 5 with a mean total harvest of 55.9 kg per tree. The mean impact of the rootstock on the tree vigour, measured upon the trunk cross section area, ranged from 148.4 cm2 on the standard rootstock P-TU-2 to 114.1 cm2 on the PHLC and 125.2 cm2 on Gisela 5 . On the standard rootstock P-TU-2, the most vigorous one according to this criterion was ‘Jacinta’ (178.0 cm2) whereas ‘Justyna’ (109.7 cm2) was the least vigorous. On the PHLC, the most vigorous was ‘Sandra’ (147.2 cm2) and the least was ‘Amid’ (94.0 cm2). The other tree characteristics were mainly dependant on the cultivar and minimally, or not at all, influenced by the rootstock vigour.

Sign in / Sign up

Export Citation Format

Share Document