Fig. 6: Chemical stability and moisture barrier performance of PDMS-coated and exposed passivation layers after accelerated in vitro (unbiased) and in vivo aging.
a, b Representative negative (N) mode ToF-SIMS surface depth profiles from 0−15 nm of the PDMS-coated and exposed regions of a 7-month explanted Chip-A sample (acquired with 0.1 nm step-size). Surface depth profiles show oxidation of the SiNX passivation with higher chlorine (Cl) and sulfur (S) impurity ions in the oxidized layer for the exposed region. c–e Comparing the thicknesses of the oxidized SiNX at different time points and aging media (in 7 m or 12 m, ‘m’ denotes month). c Comparing the thicknesses in the PDMS-coated and exposed regions after 7 months in vivo, d Comparing the thicknesses in the PDMS-coated regions after 7 and 12 months in vivo with that of a dry reference sample, and e Comparing the thicknesses in the PDMS-coated regions after 12 months exposure to accelerated in vitro and in vivo environment. f–h Average [OH−] intensities within the SiNX passivation bulk (averaged ToF-SIMS depth profile data from 50−100 nm). Data is presented as average of 4 measurement results, performed on n = 2 samples (per chip foundry) with 2 measurements per sample.
