Pattern Formation during Current Sintering

本文从理论和实验两方面研究了电流烧结过程中电导率局部下降的情况。铝掺杂ZnO为这类负反馈输运过程提供了一个范例。由于这种机制而产生的自组织模式在薄膜和散装样品的工艺参数的依赖性中进行了分析。研究了控制模式形成的可能性，例如通过施加电流作为脉冲序列或通过外部冷却。它们有可能控制绿体中比晶粒或孔大的长度尺度上的微观结构。

The microstructural evolution during current sintering is investigatedexperimentally and theoretically for the case that the conductivity dropslocally due to a reaction-diffusion process induced by the current.Aluminum-doped ZnO serves as a paradigm for this class of transportprocesses with negative feedback. The self-organized patterns that emergedue to this mechanism are being analyzed in dependence of the processparameters for thin films as well as for bulk samples. The possibility ofmanipulating the pattern formation e.g. by applying the current as apulse sequence or by external cooling are explored. Potentially they willallow control of the micro-structure on length scales larger than grain orpore size in the green body.