Ultrasonic Microspectroscopy for High-Precision Surface Characterization of Substrates for Electronics Devices

Ultrasonic microspectroscopy technologyusing the line-focus-beam (LFB) and plane-wave ultrasonic material characterization systemhas been applied to resolve material problems concerned with单加密子（LiNbO - D23 - D2, LiTaO - D23 - D2, Si, GaAs） for electronic devices and with proton-exchangedimplanted layers,epitaxial or amorphous films on the substrates used in the device fabrication processes.1reliable LFB system with high accuracy in leaky surface-acoustic-wave (LSAW) velocity measured onthe water-loaded specimen surface has been established for accurate and efficient characterizationmaterial propertiesby developing a temperature-controlled pure water supply system and a sample transfer system. Forthe system calibration, the standard specimens of GGG, Si, Ge, LiNbO - D23 - D2D23 has been developed.2. A method of super-precision measurements of latticeparameters by the X-ray diffractometer using the Bond method has been developedresulting ina very high accuracy of Δd/d<10 d -6 d for a wide Bragg angle range.3. To eliminatea serious problem of the back rection effectoccurring for thin specimens such as wafer substratesa moving average method to obtain a true velocity from apparent LSAW velocities measured as afunction of frequency and an approximated correction method useful for a number of measurementpoints been developed.4. A method of evaluating single crystals such as LiNbO D23 D2，LiTaO D23 D2，and GaAs by the LFB system has been established.5. A method of evaluating and selectingLiNbO - D23 - D2 and LiTaO - D23 - D2 substrates for SAW devices by the LFB system has beenestablished.6. A方法分析和评估proton-exchanged layers on Z-cut LiTaO - D23 - D2crystal substrates and ion-implanted layers on Si crystal substrates has been developed anddemonstrated。

Ultrasonic microspectroscopy technology, using the line-focus-beam (LFB) and plane-wave ultrasonic material characterization system, has been applied to resolve material problems concerned with single crystal substrate (LiNbOィイD23ィエD2, LiTaOィイD23ィエD2, Si, GaAs) for electronic devices and with proton-exchanged, implanted layers, epitaxial or amorphous films on the substrates used in the device fabrication processes.1. The reliable LFB system with high accuracy in leaky surface-acoustic-wave (LSAW) velocity measured on the water-loaded specimen surface has been established for accurate and efficient characterization of material properties, by developing a temperature-controlled pure water supply system and a sample transfer system. For the system calibration, the standard specimens of GGG, Si, Ge, LiNbOィイD23ィエD2, and LiTaOィイD23ィエD2 has been developed.2. A method of super-precision measurements of lattice parameters by the X-ray diffractometer using the Bond method has been developed, resulting in a very high accuracy of Δd/d<10ィイD1-6ィエD1 for a wide Bragg angle range.3. To eliminate a serious problem of the back reflection effect, occurring for thin specimens such as wafer substrates, a moving average method to obtain a true velocity from apparent LSAW velocities measured as a function of frequency and an approximated correction method useful for a number of measurement points have been developed.4. A method of evaluating single crystals such as LiNbOィイD23ィエD2, LiTaOィイD23ィエD2, and GaAs by the LFB system has been established.5. A method of evaluating and selecting LiNbOィイD23ィエD2 and LiTaOィイD23ィエD2 substrates for SAW devices by the LFB system has been established.6. A method of analyzing and evaluating proton-exchanged layers on Z-cut LiTaOィイD23ィエD2 crystal substrates and ion-implanted layers on Si crystal substrates has been developed and demonstrated.