LOCAL SLOPE SCANNING INTERFERENCE MICROSCOPE USING AN AO DEVICE, CAPABLE OF ACCURATELY MEASURING A SAMPLE SURFACE BY OBTAINING INFORMATION OF A LOCAL SLOPE OF A SAMPLE BY USING AN AO DEVICE

摘要

PURPOSE: A local slope scanning interference microscope using an AO(Acoustooptic) device is provided to stably measure a change of a slope of a sample caused by external noise by irradiating reference beams on a sample surface with signal beams together.;CONSTITUTION: A local slope scanning interference microscope(30) comprises a light source(300), a PBS(Polarizing Beam Splitter)(310), an AO device(320), an AO driving unit(330), optical detection elements(370,372), an RF(Radio Frequency) demodulator(380), a lock-in AMP(Amplifier)(386), a function generator(384), and a control unit(390). The AO driving unit drives the AO device according to a modulation frequency(f_RF) dithering within a frequency variable range on a basis of a center-modulated frequency(f_RF0). The optical detection elements detect interference signals of signal lights and reference lights. The RF demodulator demodulates the interference signals by using the modulation frequency, thereby outputting. The lock-in AMP demodulates signals supplied from the RF modulator by using a dithering frequency(f_dithering), thereby outputting. The function generator generates a pre-set amplitude and dithering signals having the dithering frequency, supplies the dithering signals to the AO driving unit, and supplies the dithering frequency to the lock-in AMP. The control unit detects information with respect to a sample by using the signals output by the lock-in AMP.;COPYRIGHT KIPO 2013;[Reference numerals] (330) AOM driving unit; (380) RF demodulator; (384) Function generator; (386) Lock-in amplifier