单晶铌酸锂薄膜的转移制备技术研究

Transfer preparation technology of single crystal lithium niobate thin films

以苯并环丁烯(Benzocyclobutene,BCB)作为键合层,采用离子注入剥离技术制备了Y36切型的单晶铌酸锂薄膜材料。经过对BCB键合层的前烘时间和退火曲线进行系统的研究,克服了由于铌酸锂和BCB之间热膨胀系数不匹配所导致的铌酸锂薄膜开裂问题,获得了高质量的Y36切型单晶铌酸锂薄膜材料。此外,通过在晶圆键合之前预先制备图形化的金属层,获得了带有下电极功能层的单晶铌酸锂薄膜,可应用于薄膜体声波谐振器等具有金属-绝缘层-金属结构的器件。

Single crystalline Y36-cut lithium niobate thin films were fabricated by means of crystal ion slicing(CIS)technique with Benzocyclobutene(BCB)as the bonding medium.The prebaking conditions of BCB and the annealing curve were systematically investigated and optimized,and high quality single crystalline Y36-cut lithium niobate thin films were obtained by overcoming the cracking problem caused by the mismatch of thermal expansion coefficients between lithium niobate and BCB.Moreover,A single crystalline lithium niobate film with bottom electrode was obtained by prefabricating a patterned metal layer before the wafer bonding,which can be applied in the devices with metal-insulator-metal structures,such as film bulk acoustic resonator.