Study on Surface acoustic wave/semiconductor functional devices

(1)We提出了一种基于外延剥离工艺的新的制造技术。我们研究了剥离和键合工艺的最佳条件，成功地制作了半导体薄膜无损伤的GaAs MESFET、Schttoky二极管。(2)We改进了外延剥离工艺，并在晶片处理、蚀刻和键合方面取得了进展。利用这些改进的工艺，我们制作了SAW-半导体共集成器件的基本电路，如自适应滤波器，并成功地测量了基本特性。我们也利用X光与原子力显微镜研究了ST切割石英的表面微观形貌特征，并探讨这些特征对元件特性退化的影响。(3)We还采用衬底去除工艺释放GaAs外延膜，GaAs外延膜生长在GaAs衬底上的AlAs薄膜上，并采用Au-Sn共晶键合工艺将GaAs薄膜键合在Y-ZLINbO 3衬底上。(4)We提出了一种利用石英晶体的x轴反转现象制作AT切谐振器的单片集成技术。已经清楚，在AT切割板上形成的x-ais反转区域非常有效地减少了在板上形成的谐振器之间的机械耦合。这表明在AT切割板上的谐振器阵列的可能性。(5)We研究了橡胶敏感膜压电气体传感器，实验表明，不同种类的橡胶敏感膜具有不同的选择性，可以作为气体传感器使用。

(1)We proposed new fabrication technology based on epitaxial liftoff process. We investigated the optimal condition for liftoff and bonding processes and succeeded in fabricating GaAs MESFET,Schttoky diode without any damage in semiconductor films.(2)We improved the epitaxial lift-off process and advance in wafer handing, etching and bonding. Using these improved processes, We have fabricated basic circuit for SAW-semiconductor co-integrated devices such adaptive filter and succeeded measuring basic characteristics. We also investigated suface microspico feature of ST-cut quartz using X-ray and AFM.We are studying the effects of these features on degradation of device characteristics.(3)We also applied substrate removal process to release GaAs epitaxial film, which is grown on the AlAs thin film on GaAs substrate and adapted Au-Sn eutectic bonding process to bonding GaAs film on the Y-ZLINbO3 substrate.(4)We proposed a monolithic integration technique for AT-cut resonator using the x-axis inversion phenomenon of quartz. It was clarified that an x-aiis inversion area formed on an AT-cut plate very effectively reduces the mechanical coupling between resonators formed on the plate. This suggests the apossibility of resonator arrays on an AT-cut plate.(5)We also studied piezoeletiic gasses sensor using rubber sensing film and experiments showed that sensors using various kinds of film have different selectivity which is sufficient for application as gas sensors.