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用LiTaO_3单晶片制成了诸如SAW电视中频滤波器、电视广播发射机残余边带滤波器及用于视频磁带录像调谐器的SAW谐振器等多种SAW器件.这些器件现已投入批量生产和实际应用.它们的突出特点是温度稳定性好、传输损耗小、杂波响应小、重复性可靠性高并且适于批量生产.这一些远优于用其它材料作基片的器件,能很好地满足信息处理和通讯系统电子线路设计的要求.在这些成就中,在X切LiTaO_3晶体基片上发现的一种传输方向以及SAW级的LiTaO_3单晶生长技术的改进都起了极重要的作用.当SAW在X切的基片上沿旋转Y112°传播时,体波响应可抑制到-40分贝以下并且有很低的温度系数(～18ppm/℃)和适当的耦合系数(K~2约为0.75%).用铂铑坩埚和提拉技术沿X轴生成的SAW级的LiTaO_3单晶长达130毫米,直径达62—75毫米.
A wide range of SAW devices such as SAW TV IF filters, TV broadcast transmitter residual sideband filters and SAW resonators for video tape recorders have been made using LiTaO 3 single wafers and these devices are now in volume production and real Applications. Their salient features are good temperature stability, low transmission loss, small clutter response, high reproducibility, and good mass production, which is far superior to devices made from other materials for the substrate, Meet the requirements of the electronic circuit design of information processing and communication system.In these achievements, a transmission direction found on the X-cut LiTaO_3 crystal substrate and the improvement of the SAW-grade LiTaO_3 single crystal growth technology all play an important role. The SAW can be suppressed to below -40 dB with a very low temperature coefficient (~ 18 ppm / ° C) and a suitable coupling coefficient (K ~ 2 about 0.75% ). The SAW-grade LiTaO_3 single crystal, formed along the X-axis with a platinum-rhodium crucible and a lift-off technique, has a length of 130 mm and a diameter of 62-75 mm.