Frequency determination in nondestructive test of semiconductor devices with ultrasound heating

Abstract

The infrared-optical beam induced resistance change (IR-OBIRCH) method is widely used to localize faults of semiconductor devices. Prior to the fault localization, the IR-OBIRCH generally requires a decapsulation of mold resin that covers the semiconductor devices. As an alternative, without the need for decapsulation, the authors propose the ultrasonic beam induced resistance change (SOBIRCH) method. This research examined a determination method of the optimal ultrasound frequency in order to improve the signal intensity of SOBIRCH even if the speed of sound and the thickness of mold resin are unknown. The resonant frequency estimated by using frequency component of signals of reflected wave agreed with the ultrasound frequency that maximized the intensity of SOBIRCH signal. The frequency dependence of SOBIRCH signal was also estimated. This research demonstrated that the proposed frequency determination method can estimate the resonant frequency on the fault observation of a practical device.

Multi-mode 3D ultrasonic phased array imaging method using piezoelectric and laser ultrasonic system (PLUS)

“…To avoid catastrophic accidents, the reliable and accurate nondestructive measurement of cracks is indispensable. Among various nondestructive testing (NDT) methods, ultrasonic testing (UT) [1][2][3][4][5][6][7] is one of the most practical methods for internal defects since UT is highly sensitive to cracks. 1,8,9) Although conventional UT was based on the measurement of defect echo, ultrasonic phased array (PA) has recently become one of the primary means in industrial fields because of its excellent imaging capability.…”

Integrity assessment of turbine generator rotor wedges based on their resonance characteristics

“…Nonlinear methods such as imaging using harmonics of airborne ultrasound [16,17] and nonlinear scattering from closed cracks [18][19][20] have also been proposed. In recent years, resistance detection by ultrasonic heating [21] and defect detection by guided wave generation using an airborne ultrasonic phased array [22] have been reported.…”

Non-contact identification of moisture content of fabric based on analysis of broadband acoustic signals using multiple-frequency air ultrasonic transducer system

“…[5][6][7][8][9][10][11][12][13][14][15][16][17] Engineering applications related to noncontact operation, [18][19][20][21][22][23][24] which utilize the characteristics of ultrasonic waves such as high directivity and resonance, are being actively studied. [25][26][27][28][29][30][31][32][33] Our group has been conducting continuous research using ultrasonic transducers, including the development of acoustic sensing and acoustic levitation using air ultrasonic transducers. 6,7,[21][22][23] The practical application of non-contact methods is one of the most critical areas of research today, owing to the current social problems such as the spread of infectious diseases.…”