Crystal Growth of nitride single crystals of high purity with the ammonothermal method

该项目的第二个供资期涉及扩大和进一步开发用于氮化物单晶生长的氨酸法和氨硼法。在这种情况下，其他子项目的最新成果将应用于基本工艺，不仅可以获得超越现有技术的优化工艺，而且可以获得晶体生长过程中正在进行的工艺的综合视图。 将评估无意杂质的来源和运输，并根据工艺参数和生长系统的化学性质检查其掺入晶体的情况。除了实验工作和直接相关的，流动模式和工艺参数对温度和流量分布的影响将进一步研究与30模拟，这将有助于涉及到目前为止在文献中未考虑的影响。此外，根据第一阶段的新发现，将开发一个氨氮系统的化学模型，该模型将解释以前未知的方面，如矿化物的反向运输或化学spezies的分布。目前还没有这样的模型。在该项目的后期，所获得的关于氮化物的氨合成的知识将被转移到新的功能氮化物晶体的生长中。TP 1在第一阶段进行的氮化物化合物的研究表明，特别是具有纤锌矿型结构的此类化合物是合成氨的非常有前途的候选物。基于子项目1和2关于中间体和新矿化剂的实验和研究，将针对半导体材料InN和Zn 3 N2以及三元锌-IV-氮化物如ZnSiN 2、ZnGeN 2和ZnSnN 2的生长。迄今为止，这些材料不能作为块状晶体材料生产。然而，可以预期这些化合物的高潜力作为现有GaN、InN和AlN系统的替代物。因此，该项目将路径的方式来获得一个新的材料系统。

The second funding period of this project deals with the extension and further development of the ammonoacidic and ammonobasic process for the growth of nitride single crystals. In this context , the recent results of the other subprojects will be applied to the basic processes in order to not only get an optimized process beyond state of the art, but to get an integrated view of the ongoing processes during crystal growth. The sources and transport of unintentional impurities will be evaluated and their incorporation into the crystals depending on the process parameters and the chemistry of the growth system are examined. In addition to the experimental work and directly related thereto, the flow pattern and the influence of the process parameters on the temperature and flow distribution will be further investigated with 30 simulations, which will help to involve so far in literature unconsidered effects. Moreover, a chemical model of the ammonothermal system will be developed, based on the new finding from period one, which will account for previously unconsiderd aspects like back transportation of the mineralizes or distribution of chemical spezies. Such a model does not exist so far.Later on in the project, the obtained knowledge with regard to the ammonothermal synthesis of nitrides will be transferred to the growth of new functional nitride crystals . The studies of nitride compounds performed in the first period by TP 1, revealed that especially such compounds with a Wurtzite-type structure are very promising candidates for an ammonothermal synthesis . Based on the experiments and investigations of the subprojects 1 and 2 concerning intermediates and new mineralizers, the growth of the semiconductor materials lnN and Zn3N2 and of the ternary Zinc-IV-nitr ides, like ZnSiN2 , ZnGeN2 , and ZnSnN2 , will be targeted . These materials could not be produced as bulk crystalline material so far. However, a high potential of these compounds could be expected as a alternative to the existing GaN, lnN, and AIN system. So the project will path the way to access a new material system.