铌酸锂单晶薄膜材料

摘要/Abstract

摘要： 铌酸锂晶体集电光、声光和非线性光学等物理特性于一身,且透光范围宽,作为一种重要的光学材料被广泛应用于通信、传感等领域。通过离子注入与直接键合的方式制备出的铌酸锂单晶薄膜材料,保留了铌酸锂体材料的优秀物理特性,并且具有高折射率对比度的优点,使光子器件在集成度和性能上都得到了很大程度的提升。本文介绍了铌酸锂薄膜的制备及应用,展示了直径6英寸(1英寸=2.54 cm)的铌酸锂单晶薄膜。将硅单晶薄膜覆盖在铌酸锂单晶薄膜上面,形成一种新型的复合薄膜材料,结合了铌酸锂出色的光学性能和硅出色的电学性能,本文报道了直径3英寸的复合薄膜材料,X射线证明硅薄膜是单晶结构,这种复合薄膜在未来的集成光电芯片中具有应用潜力。

关键词: 铌酸锂, 薄膜, 离子注入, 直接键合, 化学机械抛光

Abstract: Lithium niobate crystals have excellent electro-optic, acousto-optic and nonlinear optical properties, and have broad transmission window. As an important optical material, it is widely used in the fields of communication and sensing. Single-crystal lithium niobate thin film (lithium niobate on insulator, LNOI) prepared by ion implantation and direct bonding retains the excellent physical properties of lithium niobate bulk material, and it has large refractive index contrast. Photonic devices based on this material have been greatly improved in terms of integration and device performance. The preparation process and applications of LNOI is introduced in this paper, and a 6-inch LNOI is demonstrated. A hybrid thin film can be formed by covering a single-crystal silicon thin film on the top of a LNOI. This hybrid thin film combines the excellent optical properties of LN and excellent electronic properties of silicon. 3-inch hybrid thin film is reported in this paper. X-ray diffraction shows that the silicon thin film is single-crystal. This hybrid material will have potential applications in the future integrated optoelectronic chips.

Key words: lithium niobate, thin film, ion implantation, direct bonding, chemical mechanical polishing

中图分类号:

O734

李青云, 朱厚彬, 张洪湖, 张秀全, 胡卉. 铌酸锂单晶薄膜材料[J]. 人工晶体学报, 2021, 50(4): 716-723.

LI Qingyun, ZHU Houbin, ZHANG Honghu, ZHANG Xiuquan, HU Hui. Single-Crystal Lithium Niobate Thin Films[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2021, 50(4): 716-723.

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