Growth rate has a direct impact on the productivity of nitride LED production. Atmospheric pressure growth of GaN with a growth rate as high as 10/zm/h and also Alo.lGao.gN growth of 1μm/h by using 4 inch by 11 produ...Growth rate has a direct impact on the productivity of nitride LED production. Atmospheric pressure growth of GaN with a growth rate as high as 10/zm/h and also Alo.lGao.gN growth of 1μm/h by using 4 inch by 11 production scale MOVPE are described. XRD of （002） and （102） direction was 200 arcsec and 250 arcsec, respectively. Impact of the growth rate on productivity is discussed.展开更多
We have developed a one-step process for the synthesis of basic magnesium sulfate （5Mg（OH）2-MgSO4-3H20, abbreviated as 513MOS） whiskers from MgSO4,7H20 and MgO by refluxing at atmospheric pressure. The process sho...We have developed a one-step process for the synthesis of basic magnesium sulfate （5Mg（OH）2-MgSO4-3H20, abbreviated as 513MOS） whiskers from MgSO4,7H20 and MgO by refluxing at atmospheric pressure. The process shows potential for the low-cost mass production of controlled- structure whiskers. Their 0.3-1.0 μm diameter and 40-80 μm length correspond to an aspect ratio of 40-260. The 513MOS whisker morphology is related closely to MgSO4 concentration and reflux time. The optimized MgSO4 concentration is 1.2-1.5 mol/L with a 25-30 h reflux time. X-ray diffractometry revealed that the b-axis is the predominant growth direction of the whiskers. Their growth mechanism is by the relatively slow liquid-phase deposition of Mg2＋, OH-, and SO42-. The long reaction time and high MgSO4 concentration are conducive to the formation of 513MOS whiskers under gentle reaction conditions. Porous MgO whiskers with a fibrous structure were obtained after calcination of the 513MOS whiskers at 1020 ℃.展开更多
文摘Growth rate has a direct impact on the productivity of nitride LED production. Atmospheric pressure growth of GaN with a growth rate as high as 10/zm/h and also Alo.lGao.gN growth of 1μm/h by using 4 inch by 11 production scale MOVPE are described. XRD of （002） and （102） direction was 200 arcsec and 250 arcsec, respectively. Impact of the growth rate on productivity is discussed.
文摘We have developed a one-step process for the synthesis of basic magnesium sulfate （5Mg（OH）2-MgSO4-3H20, abbreviated as 513MOS） whiskers from MgSO4,7H20 and MgO by refluxing at atmospheric pressure. The process shows potential for the low-cost mass production of controlled- structure whiskers. Their 0.3-1.0 μm diameter and 40-80 μm length correspond to an aspect ratio of 40-260. The 513MOS whisker morphology is related closely to MgSO4 concentration and reflux time. The optimized MgSO4 concentration is 1.2-1.5 mol/L with a 25-30 h reflux time. X-ray diffractometry revealed that the b-axis is the predominant growth direction of the whiskers. Their growth mechanism is by the relatively slow liquid-phase deposition of Mg2＋, OH-, and SO42-. The long reaction time and high MgSO4 concentration are conducive to the formation of 513MOS whiskers under gentle reaction conditions. Porous MgO whiskers with a fibrous structure were obtained after calcination of the 513MOS whiskers at 1020 ℃.
