In-situ XRD study at cryogenic temperatures

Several materials are explored in microelectronics for application such as interconnections for 3D integration or in quantum computing applications. A key parameter is the superconducting properties of materials such as Ta, Sn with a critical temperature at 3.74K. One issue is that such materials undergo phase transition. For example, Sn undergoes a pase transition at 286K (13°C), from a body centred tetragonal phase Beta-Sn, to diamond cubic one inducing a huge volume increase of 27%, resulting in cracks of matter and in transformation into powder.
In the frame of this proposal, we will use the cryostat developped at BM02 to beamline to reach low temperature (6 K) to study the phase transition of such materials.

本研究针对微电子领域多款材料展开探索，其应用场景涵盖三维集成互连结构以及量子计算相关场景。其中核心表征参数为材料的超导特性，以钽（Ta）、锡（Sn）为例，二者的临界转变温度为3.74K。但这类材料普遍存在相变问题。例如，锡（Sn）在286K（即13℃）时会发生相变：从体心四方相的β-Sn转变为金刚石立方相，伴随27%的体积膨胀，最终引发材料开裂并粉化。在本项目框架内，我们将借助BM02光束线站自研的低温恒温器，实现6K的低温环境，以此开展上述材料的相变研究。