Microscopic Analysis of Stress-Induced Leakage Current in Stressed Gate SiO₂Films Using Conductive Atomic Force Microscopy

Conductive Atomic Force Microscopy Analysis for Local Electrical Characteristics in Stressed SiO2 Gate Films

“…In this case, the electric field is increased locally at the hole-trapped site due to the bandbending of the SiO 2 conduction band, resulting in the enhanced FN current. 9) In contrast, no current spots were observed in the holedetrapped sample shown in Fig. 4(b), even though the same substrate voltage was applied for taking the image.…”

“…9) In C-AFM images of stressed SiO 2 films, leakage current spots of nanometer scale were successfully observed. The observed current spots show characteristic behaviors similar to the transient stress induced leakage current which can be detected by macroscopic electrical measurements using the MOS capacitors.…”

Local Current Leakage Characterization in La2O3-Al2O3 Composite Films by Conductive Atomic Force Microscopy

“…1. The leakage currents from the spots (1)- (3) have large values compared with the average currents at lower voltages and these currents do not increase very much at higher voltages. This phenomenon suggests current conduction via defects existing in the film.…”

“…Figure 1 shows I-V characteristics obtained from the MOS capacitor and average current density measured from C-AFM current images taken at various oxide voltages. An effective contact area of a C-AFM tip is assumed to be 2×10 -12 cm 2 [3] . The voltage dependence of current densities measured from the C-AFM agrees well with the I-V characteristic obtained from the MOS capacitor.…”

“…Conductive atomic force microscopy (C-AFM) is a powerful tool to analyze the local morphological and electrical properties in gate dielectric films [1,2] . We have elucidated thus far local current leakage and degradation processes in stressed SiO 2 films using C-AFM [3][4][5][6][7] .…”