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, [1] 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.