排序方式: 共有103条查询结果,搜索用时 15 毫秒
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In0.5(Ga1-xAlx)0.5P合金的掺杂生长特性 总被引:1,自引:1,他引:0
利用LP-MOCVD分别生长Zn和S掺杂的In0.5(Ga1-xAlx)0 5P外延层,研究生长温度、掺杂源流量、V/Ⅲ比、Al组分以及衬底晶向偏离等生长条件对外延层掺杂浓度的影响.实验结果表明:降低生长温度和Al含量、增加DEZn流量、选择由(100)向(111)A偏6~15的衬底都有利于增加IRGaAlP合金中Zn的掺杂浓度;提高生长温度和增加SIH4流量、减小Al含量和V/Ⅲ比,都有助于增加Si掺杂浓度,而衬底晶向对Si掺杂浓度无影响. 相似文献
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张国义付予锦吴金城徐新然秦明刚熊书书张仟春 《理化检验(化学分册)》2018,(10):1117-1121
基于正丁醚在纳米氧化锌材料表面的催化发光现象设计并制造了正丁醚催化发光传感器,并提出了一种快速测定空气中正丁醚的方法。在检测波长为440nm,反应温度为288℃,载气流量为280mL·min-1条件下,正丁醚的质量浓度在30.0~2 000mg·m-3内与其催化发光强度呈线性关系,检出限(3S/N)为12.0mg·m-3。将上述方法用于空气样品中正丁醚含量的测定,其测定结果与气相色谱-质谱法所得结果吻合。 相似文献
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用正向电压法、管脚法和蓝白比法等三种方法测量GaN基白光LED的结温,获得了较为准确的结温,误差可以控制在4℃以内.正向电压法在恒定电流的条件下,得到了正向电压与结温的线性关系;蓝白比法在不同环境温度和不同注入电流两种情况下,都得到了蓝白比与结温较好的线性关系.提出了蓝白比法可能的物理机制,提高环境温度和增大注入电流都会使结温升高,蓝光峰值波长也会改变,这两个因素都会影响荧光粉的激发和发光效率.降低结温需要考虑的主要因素有白光LED的接触电阻、串联电阻和外量子效率,封装材料的热导率,反射杯和管脚的设计,以及空气散热部分的散热面积等. 相似文献
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Strain Effect on Photoluminescences from InGaN MQWs with Different Barriers Grown by MOCVD 下载免费PDF全文
InGaN/GaN MQWs, InGaN/AlGaN MQWs and InGaN/AlInGaN MQWs are grown on (0001) sapphire substrates by MOCVD. Membrane samples are fabricated by laser lift-off technology. The photoluminescence spec-ra of membranes show a blue shift of peak positions in InGaN/GaN MQWs, a red shift of peak positions in InGaN/AlGaN MQWs and no shift of peak positions in InGaN/AIlnGaN MQWs from those of samples with substrates. Different changes in Raman scattering spectra and HR-XRD (0002) profile of InGaN/AlInGaN MQWs, from those of InGaN/GaN MQWs and InGaN/AlGaN MQWs, are observed. The fact that the strain changes differently among InGaN MQWs with different barriers is confirmed. The AIlnGaN barrier could adjust the residual stress for the least strain-induced electric field in InGaN/AIlnGaN quantum wells. 相似文献
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采用金属有机化学气相沉积(MOCVD)技术以蓝宝石为衬底在n型GaN单晶层上生长了InGaN/GaN多量子阱结构外延薄膜,利用高分辨X射线衍射(HRXRD),卢瑟福背散射/沟道(RBS/channeling),以及光致发光(PL)技术对InGaN/GaN多量子阱结构薄膜分别进行了平均晶格常数计算、In原子替位率计算和In组分的定量分析.研究表明:InGaN/GaN多量子阱的水平和垂直方向平均晶格常数分别为aepi=0.3195nm,cepi=0.5198nm,In原子的替位率为99.3%,利用HRXRD和RBS/channeling两种分析技术计算In的组分分别是0.023和0.026,并与样品生长时设定的预期目标相符合,验证了两种实验方法的准确性;而用室温条件下的光致发光谱(PL)来计算InGaN/GaN多量子阱中In的组分是与HRXRD和RBS/channeling的实验结果相差很大,说明用PL测试In组分的方法是不适宜的.
关键词:
InGaN/GaN多量子阱
高分辨X射线衍射
卢瑟福背散射/沟道
光致发光 相似文献
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Thin tungsten nitride (WNx) films were produced by reactive DC magnetron sputtering of tungsten in an Ar-N2 gas mixture. The films were used as Schottky contacts on AlGaN/GaN heterostructures. The Schottky behaviours of WNx contact was investigated under various annealing conditions by current-voltage (I-V ) measurements. The results show that the gate leakage current was reduced to 10-6 A/cm2 when the N2 flow is 400 mL/min. The results also show that the WNx contact improved the thermal stability of Schottky contacts. Finally, the current transport mechanism in WNx/AlGaN/GaN Schottky diodes has been investigated by means of I-V characterisation technique at various temperatures between 300 K and 523 K. A TE model with a Gaussian distribution of Schottky barrier heights (SBHs) is thought to be responsible for the electrical behaviour at temperatures lower than 523 K. 相似文献