A Polymeric Planarization Strategy for Versatile Multiterminal Electrical Transport Studies on Small, Bulk Crystals
A Polymeric Planarization Strategy for Versatile Multiterminal Electrical Transport Studies on Small, Bulk Crystals
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DOI：
10.1021/acsaelm.2c01149
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发表时间：
2022-08
影响因子：
4.7
通讯作者：
Huandong Chen;A. Avishai;Mythili Surendran;J. Ravichandran
中科院分区：
文献类型：
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作者：
Huandong Chen;A. Avishai;Mythili Surendran;J. Ravichandran
我们报告了一种器件制造策略，使用基于光刻的技术在小型（<1 mm）块体量子材料上制作多端子电接触以进行电传输研究。将晶体嵌入聚合物介质中以平坦化顶部表面，然后直接应用标准光刻和微加工技术形成具有各种几何形状的电极。这种方法克服了晶体厚度和横向尺寸对建立电接触的限制。我们使用低应力聚合物来最大限度地减少低温下的外在热应变效应，从而可以对应变敏感的量子材料进行可靠的传输测量。晶体表面平坦化方法使得电子输运研究成为可能，例如面内各向异性、小型块状 BaTiS3 (BTS) 晶体上的霍尔测量，并为三维 (3D)/准一维 (准 1D) 块状材料上的二维 (2D) 异质集成提供了独特的机会。我们的策略适用于许多新合成的量子材料的小型、不可剥离的晶体，并为对这些新型材料进行多功能输运研究铺平了道路。
We report a device fabrication strategy of making multi-terminal electrical contacts on small (<1 mm) bulk quantum materials using lithography-based techniques for electrical transport studies. The crystals are embedded in a polymeric medium to planarize the top surface, and then standard lithography and microfabrication techniques are directly applied to form electrodes with various geometries. This approach overcomes the limitations of crystal thickness and lateral dimensions on establishing electrical contacts. We use low stress polymers to minimize the extrinsic thermal strain effect at low temperatures, which allow reliable transport measurements on quantum materials that are sensitive to strain. The crystal surface planarization method has enabled electronic transport studies such as in-plane anisotropy, Hall measurements on small, bulk BaTiS3 (BTS) crystals, and provides unique opportunities for two-dimensional (2D) heterogeneous integration on three-dimensional (3D) / quasi-one-dimensional (quasi-1D) bulk materials. Our strategy is general for many small, non-exfoliable crystals of newly synthesized quantum materials and paves the way for performing versatile transport studies on those novel materials.