Applications of C-AFM analysis techniques at advanced IC on SRAM soft failure

The application of the conductive atomic force microscope (C-AFM) has been widely reported as a useful method of failure analysis in semiconductor field of nanometer scale science and technology, Especially for hard failure and soft failure identification and localization at logic and SRAM in CMOS process. This paper will demonstrate a new application of the C-AFM to identify the electric characteristic of SRAM soft failure in CMOS process. After taking electrical measurement, plain view SEM and cross-section TEM will reveal and understand the physical root cause of the electrical failure. After that, the principle of application for C-AFM on this SRAM soft failure analysis will be discussed.