中国物理B ›› 2022, Vol. 31 ›› Issue (9): 96801-096801.doi: 10.1088/1674-1056/ac7867
Jing Wang(王静)1, Meysam Bagheri Tagani2, Li Zhang(张力)1,†, Yu Xia(夏雨)1, Qilong Wu(吴奇龙)1, Bo Li(黎博)1, Qiwei Tian(田麒玮)1, Yuan Tian(田园)1, Long-Jing Yin(殷隆晶)1, Lijie Zhang(张利杰)1, and Zhihui Qin(秦志辉)1,‡
Jing Wang(王静)1, Meysam Bagheri Tagani2, Li Zhang(张力)1,†, Yu Xia(夏雨)1, Qilong Wu(吴奇龙)1, Bo Li(黎博)1, Qiwei Tian(田麒玮)1, Yuan Tian(田园)1, Long-Jing Yin(殷隆晶)1, Lijie Zhang(张利杰)1, and Zhihui Qin(秦志辉)1,‡
摘要: Two-dimensional (2D) semiconductors, such as lead selenide (PbSe), locate at the key position of next-generation devices. However, the ultrathin PbSe is still rarely reported experimentally, particularly on metal substrates. Here, we report the ultrathin PbSe synthesized via sequential molecular beam epitaxy on Ag(111). The scanning tunneling microscopy is used to resolve the atomic structure and confirms the selective formation of ultrathin PbSe through the reaction between Ag5Se2 and Pb, as further evidenced by the theoretical calculation. It is also found that the increased accumulation of Pb leads to the improved quality of PbSe with larger and more uniform films. The detailed analysis demonstrates the bilayer structure of synthesized PbSe, which could be deemed to achieve the 2D limit. The differential conductance spectrum reveals a metallic feature of the PbSe film, indicating a certain interaction between PbSe and Ag(111). Moreover, the moiré pattern originated from the lattice mismatch between PbSe and Ag(111) is observed, and this moiré system provides the opportunity for studying physics under periodical modulation and for device applications. Our work illustrates a pathway to selectively synthesize ultrathin PbSe on metal surfaces and suggests a 2D experimental platform to explore PbSe-based opto-electronic and thermoelectric phenomena.
中图分类号: (Scanning tunneling microscopy (including chemistry induced with STM))