Study on Surface acoustic wave/semiconductor functional devices

(1)提出了基于外延提拉工艺的新的制备工艺。研究了剥离和键合的最佳工艺条件，在不损伤半导体薄膜的情况下，成功地制作了GaAsMESFET、Schttoky二极管。(2)改进了外延剥离工艺，在晶片加工、刻蚀和键合方面取得了进展。利用这些改进的工艺，我们制作了自适应滤波器等SAW-半导体共集成器件的基本电路，并成功地测试了基本特性。我们还利用X射线和原子力显微镜研究了ST切石英的表面微结构特征，研究了这些特征对器件性能退化的影响。(3)我们还采用了衬底去除工艺来释放在GaAs衬底上生长的GaAs外延膜，并采用了Au-Sn共晶键合工艺来键合Y-ZLINbO_3衬底上的GaAs膜。(4)提出了一种利用石英的x轴反转现象来实现AT切谐振器的单片集成技术。研究表明，在AT切板上形成的x-AlI s反转区非常有效地减少了板上形成的谐振器之间的机械耦合。对橡胶敏感膜压电式气体传感器进行了研究，实验表明，使用不同种类的橡胶敏感膜制作的传感器具有不同的选择性，足以作为气敏传感器使用。

(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.