Application and Optimization of Automated ECCI Mapping to the Analysis of Lowly Defective Epitaxial Films on Blanket or Patterned Wafers

Abstract Although the physical limits of CMOS scaling should have been reached years ago, the process is still ongoing due to continuous improvements in material quality and analytical techniques. This paper describes one such technique, electron channeling contrast imaging (ECCI), explaining how it is used to analyze nanoscale features and defects. ECCI allows for fast, nondestructive characterization and has the potential for extremely low detection limits. The detection of low-level defects requires measurements over large areas (usually with the help of automation) to obtain statistically relevant data. For example, automated ECCI mapping routines have been shown to quantify crystal defect densities as low as 1 x 105 cm-2 in epitaxially grown Si0.75Ge0.25. The paper presents various methods to reduce measurement time without compromising sensitivity. It also explains how the mapping routine can be optimized to detect extended crystalline defects in III/V layers, selectively grown on shallow trench isolation patterned Si wafers.