Evaluation of functional materials and devices using atomic force microscopy with ultrasonic measurements

Modem functional materials and devices require thorough testing for safety and reliability. Here, we describe solutions to meet this requirement in the field of scanning probe microscopy, and the most practical approach among them; ultrasonic atomic force microscopy (UAFM), In this review, we focus on evaluation of subsurface defects with scientific and technological importance, such as domains of ferroelectric materials and subsurface delamination of metal electrodes on microdevices. In addition, we show the development and application of the lateral bending (LB) mode and lateral modulation atomic force microscopy (LM-AFM) with applications in nanomaterials including carbon nanotube composites and discuss their future development in combination with UAFM.