This presentation provides an introduction to atomic force microscopy (AFM) and its many uses in semiconductor failure analysis. It provides examples showing how AFM is used to obtain information on electric fields, surface potential, current, resistance, capacitance, impedance, carrier concentration, mechanical contact (height and energy dissipation), temperature, and composition. It also addresses a number of related issues including the use of external stimuli, sample preparation requirements, and probe tip selection.

Methods are available to measure conductivity, charge, surface potential, carrier density, piezo-electric and other electrical properties with nanometer scale resolution. One of these methods, scanning microwave impedance microscopy (sMIM), has gained interest due to its capability to measure the full impedance (capacitance and resistive part) with high sensitivity and high spatial resolution. This paper introduces a novel data-cube approach that combines sMIM imaging and sMIM point spectroscopy, producing an integrated and complete 3D data set. This approach replaces the subjective approach of guessing locations of interest (for single point spectroscopy) with a big data approach resulting in higher dimensional data that can be sliced along any axis or plane and is conducive to principal component analysis or other machine learning approaches to data reduction. The data-cube approach is also applicable to other AFM-based electrical characterization modes.

High resolution scanning probe microscopy techniques combined with infrared (IR) light sources offer unique solutions to combined chemical/mechanical/electrical characterization of defects in nanoscale dimensions. Previously, atomic force microscopy combined with infrared (AFM-IR) technology has demonstrated its capability to characterize nano-patterned metal/low-k dielectrics, nanoscale organic contaminants, and directed self-assembly of block co-polymers used for advanced micro/nanofabrications. In this paper, two complementary nanoscale chemical analysis techniques, photothermal AFM-IR and scattering type scanning near-field optical microscopy, are implemented to isolate and characterize microelectronic device cross-sections. It is observed that both techniques are able to detect patterned features with a half-pitch less than 15 nm.

Dielectric film quality is one of the most important factors that will greatly impact device performance and reliability. Device level electrical analysis techniques for dielectric quality monitoring are highly needed. In this paper we present results using a new electrical AFM mode, scanning Microwave Impedance Microscopy (sMIM), for characterization of device oxide quality and for fault isolation. Devices with poor oxide quality show sMIM nano C-V and dC/dV hysteresis behavior during forward and reverse bias sweep. The sMIM capacitance sensitivity is below 1 aF allowing one to capture C-V spectra from the MOS structure formed by the gate and gate oxide with excellent signal/noise ratio and observe subtle variations between different sites.