Potassium fluoride,anhydrous
           Potassium fluoride,extra pure
           Potassium fluoride,Granular
           Silicon Dioxide
           Hydrofluoric acid
           Synthetic Cryolite
           Potassium Fluoaluminate
           Ammonium bifluoride
           Potassium Bifluoride
           Aluminium fluoride
           Sodium fluoride
           Potassium Fluorosilicate
           Fluorosilicic Acid
           Sodium silicofluoride
           Potassium Hydroxide Flakes
           Magnesium Fluoride
           Magnesium fluorosilicate
           Barium Fluoride
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Fluorite and hydrofluoric acid parity index was to 83.56 in June 22, unchanged from yesterday, the highest point in the cycle compared with 100.65 points (2012-01-09) decreased by 16.98% compared to July 15, 2013 the lowest point of 82.77 points It rose 0.95%. (Note: refers to the period since 2012-01-01). Fluorite reference price is1512.50, from 2016-4-28 since 56 days have increased by 2.682%. Hydrofluoric day downstream commodity reference price of 6540.00, starting from 2016-1-18, 157 days after another rose 9.703 percent.

Hydrofluoric acid and aluminum fluoride parity index was 111.12 in June 22, unchanged from yesterday, the highest point in the cycle compared with 115.47 points (2012-11-15) fell by 3.77%, compared with August 5, 2012 the lowest point of 96.98 point up 14.58 percent. (Note: refers to the period since 2012-01-01). Hydrofluoric acid reference price is 6540.00, starting from 2016-1-18, 157 days after another rose 9.703 percent. Day downstream aluminum fluoride commodity reference price of 6803.85, from 2016-4-27 since 57 days have decreased by 1.668%.

Si wafers with (100) or (111) oriented surfaces were treated in hydrofluoric acid (40% HF, 1 min) and then water rinsed for different times from 10 s to more than 50 h. Oxygen uptake and oxide formation were investigated by x‐ray photoelectron spectroscopy and high‐resolution electron energy‐loss spectroscopy. The initial state after the HF dip is characterized by a coverage with Si–hydride and small amounts of oxygen and fluorine. The interaction with the liquid phase of water was investigated up to the monolayer range. It shows distinct features: The first step is a rapid exchange of Si–F with H2 O to form Si–OH groups followed by a slow nucleophilic attack of OH? on surface Si–H to produce Si–OH. Growth law is logarithmic and extends to 3–5 h of water contact. The surface Si–OH act as nuclei for the attack of water on the polarized Si–SiOH backbonds. Interior Si–H and Si–OH groups develop. Further attack of OH? on interior Si–H yields Si–OH. Condensation of Si–OH forms Si–O–Si bridges and SiO2?x nuclei appear. Strain and altered surface topography lead to a changed rate of the logarithmic oxide growth. The oxide formation is accompanied by a slight corrosive attack of H2 O, leading to roughening of the surface.