【摘要】 伴随5G高频移动通信、物联网时代到来，微机电系统（micro-electro-mechanical system, MEMS）器件在国防安全、工业智能和智能生活等领域拥有巨大应用市场，基于压电效应的射频滤波器、传感器、换能器等是重点发展的关键半导体器件。为满足器件的高频、大带宽、小型化、集成化需求，具有高机电耦合系数并且与当前集成电路工艺高度兼容的AlScN薄膜是新一代压电MEMS器件的核心。AlSc二元合金靶材作为磁控溅射工艺制备AlScN薄膜的关键材料，其品质的好坏直接决定薄膜性能的优良。本文以AlScN压电薄膜在高频滤波器中的应用为背景，介绍了Sc掺杂AlN薄膜的研究进展，阐述了AlSc二元合金溅射靶材在磁控溅射制备AlScN薄膜中的优势，论述了AlSc二元合金靶材的制备方法和关键性能表征，分析了国内外在此领域的研究成果及未来的研究方向。深入开展AlSc二元合金溅射靶材的制备及应用研究，有助于推进新一代信息技术用高纯稀土靶材的研发进程，具有显著的现实意义。更多还原

【Abstract】 With the development of 5G high-frequency mobile communication and Internet of things, micro-electro-mechanical system(MEMS) devices have been widely applied in the fields of national defense and security, industrial automation, and intelligent life. Radio frequency(RF) filters, sensors and energy converters based on piezoelectric effect have been known as the key semiconductor devices in the future. Piezoelectric materials with good comprehensive properties are the basement for these semiconductor devices. AlScN thin film with high electromechanical coupling coefficient and high compatibility with current integrated circuit technology is the core of a new generation of piezoelectric MEMS devices. AlSc binary alloy target is the important material for preparing AlScN thin films by magnetron sputtering. Its quality directly determines the excellent properties of the thin films. Therefore, in this article the research progress of Sc doped AlN film was introduced, the preparation method and key performance characterization of AlSc targets with different Sc concentration was discussed, and the research results and future research direction in this field at home and abroad were reviewed. Aluminum nitride(AlN) piezoelectric film was very popular in engineering due to its good properties and low cost. However, its insufficient electromechanical coupling coefficient(Kt2～6%) and the relative narrow bandwidth of the prepared filter(1%～2.5%), made it difficult to meet the strict requirements of the new generation devices. One of the solutions for solving this problem was to add rare earth elements(Sc, Y, Er, etc.) into piezoelectric materials. Some studies showed that the piezoelectric coefficient(d33) could reach 27.6 pC·N-1, which was about 5 times that of AlN, when the doping Sc content reached 43%(atom fraction). Therefore, many scientists’ attentions had been attracted by AlScN films preparation by magnetron sputtering, which was the most promising technology for the preparation of semiconductor films because of its low cost and high efficiency. The AlSc targets’ performance directly determined the quality of the film material, such as resistivity, thickness, composition uniformity, etching performance and piezoelectric performance, as well as the arcing abnormal discharge and particle problems in the sputtering process. Different target preparation methods were selected according to different Sc contents. AlSc targets with Sc content less than 15%(atom fraction) could be produced by melting and casting to ensure the high purity. For AlSc targets with Sc content higher than 15%(atom fraction), large number of intermetallic compounds could be formed in the microstructure which could result macro segregation of components, phase uneven distribution, metallurgical defects, and poor processing performance. Therefore, powder metallurgy process for high Sc content targets was a better choice. Generally, Al and Sc powder with different size were put into a ball mill for full grinding and mixing to make them mechanically alloyed. After that, the mixed powder was put into a mold and loaded by a hydraulic press and then sintered to be a target blank. Then, it was machined to be the product. The target with 15%～50%(atom fraction) Sc could be prepared and its density could reach more than 99% in this way. Limited by the high threshold of the material preparation technology, AlSc alloy targets had been supplied only by a few target manufacturers with strong comprehensive strength, such as JX Nippon and Mining Metal Corporation(J.X metal), Materion Corporation, GRIKIN Advanced Materials Co., Ltd.(Grikin), and Huizhou Tuopu Metal Materials Co., Ltd.(TOPM) etc. Nowadays, AlSc alloy targets with Sc content less than 15%(atom fraction) had realized mass production, but AlSc alloy targets with Sc content greater than 15%(atom fraction) still had many technical difficulties. In the future, target manufacturers still needed to pursue high-quality AlSc targets with higher Sc content, higher purity, lower oxygen content, larger size, more uniform composition and microstructure through more optimized processes and advanced equipment.更多还原